Writing scheme for 1TNC ferroelectric memory bit-cell with plate-lines parallel to a bit-line and with individual switches and control on the plate-lines of the bit-cell

ABSTRACT

A memory is provided which comprises a capacitor including non-linear polar material. The capacitor may have a first terminal coupled to a node (e.g., a storage node) and a second terminal coupled to a plate-line. The capacitors can be a planar capacitor or non-planar capacitor (also known as pillar capacitor). The memory includes a transistor coupled to the node and a bit-line, wherein the transistor is controllable by a word-line, wherein the plate-line is parallel to the bit-line. The memory includes a refresh circuitry to refresh charge on the capacitor periodically or at a predetermined time. The refresh circuit can utilize one or more of the endurance mechanisms. When the plate-line is parallel to the bit-line, a specific read and write scheme may be used to reduce the disturb voltage for unselected bit-cells. A different scheme is used when the plate-line is parallel to the word-line.

CLAIM OF PRIORITY

This application is a Continuation Application of, and claims thebenefit of priority to, U.S. patent application Ser. No. 17/529,258,filed on Nov. 17, 2021, and titled, “Pulsing Scheme for a FerroelectricMemory Bit-Cell to Minimize Read or Write Disturb Effect and RefreshLogic,” which is incorporated by reference in its entirety for allpurposes.

BACKGROUND

The standard memory used in processors is static random-access memory(SRAM) or dynamic random-access memory (DRAM), and their derivatives.These memories are volatile memories. For example, when power to thememories is turned off, the memories lose their stored data.Non-volatile memories are now commonly used in computing platforms toreplace magnetic hard disks. Non-volatile memories retain their storeddata for prolonged periods (e.g., months, years, or forever) even whenpower to those memories is turned off. Examples of non-volatile memoriesare magnetic random-access memory (MRAM), NAND, or NOR flash memories.These memories may not be suitable for low power and compact computingdevices because these memories suffer from high write energy, lowdensity, and high-power consumption.

The background description provided here is for the purpose of generallypresenting the context of the disclosure. Unless otherwise indicatedhere, the material described in this section is not prior art to theclaims in this application and are not admitted being prior art byinclusion in this section.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments of the disclosure will be understood more fully from thedetailed description given below and from the accompanying drawings ofvarious embodiments of the disclosure, which, however, should not betaken to limit the disclosure to the specific embodiments, but are forexplanation and understanding only.

FIG. 1 illustrates a set of plots showing behavior of a ferroelectriccapacitor, a paraelectric capacitor, and a linear capacitor.

FIG. 2A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises ferroelectric (FE) memory bit-cell,where an individual memory bit-cell includes one transistor and onecapacitor (1T1C) with a plate-line (PL) parallel to a bit-line (PL),where the corresponding logic is to apply word-line boosting, inaccordance with some embodiments.

FIG. 2B illustrates a high-level endurance enhancement architecture forthe FE memory, in accordance with some embodiments.

FIG. 2C illustrates a flowchart of memory endurance for the FE memory,in accordance with some embodiments.

FIG. 2D illustrates an FE memory with word-line repeaters, whereinmemory arrays of the FE memory have 1T1C bit-cells with the PL parallelto the BL, in accordance with some embodiments.

FIG. 2E illustrates a timing diagram for write operation for 1T1C FEmemory bit-cells, where the write operation involves word-line boosting,in accordance with some embodiments.

FIG. 2F illustrates a timing diagram for read operation for 1T1C FEmemory bit-cells, where the read operation involves word-line boosting,in accordance with some embodiments.

FIG. 3A illustrates a three-dimensional (3D) view of a 1T1C FE bit-cellwith the PL parallel to the BL, where the transistor is a planartransistor and where the capacitor is a planar capacitor, in accordancewith some embodiments.

FIG. 3B illustrates a 3D view of a 1T1C FE bit-cell with PL parallel tothe BL, where the transistor is a planar transistor and where thecapacitor is a planar capacitor with partially wrapped encapsulation, inaccordance with some embodiments.

FIG. 3C illustrates a 3D view of a 1T1C FE bit-cell with PL parallel tothe BL, where the transistor is a planar transistor and where thecapacitor is a planar capacitor with wrapped encapsulation, inaccordance with some embodiments.

FIG. 3D illustrates a 3D view of a 1T1C FE bit-cell with the PL parallelto the BL, where the transistor is a non-planar transistor and where thecapacitor is a planar capacitor, in accordance with some embodiments.

FIG. 3E illustrates a 3D view of a 1T1C FE bit-cell with the PL parallelto the BL, where the transistor is a non-planar transistor and where thecapacitor is a planar capacitor with partially wrapped encapsulation, inaccordance with some embodiments.

FIG. 3F illustrates a 3D view of a 1T1C FE bit-cell with the PL parallelto the BL, where the transistor is a non-planar transistor and where thecapacitor is a planar capacitor with wrapped encapsulation, inaccordance with some embodiments.

FIG. 4A illustrates a pillar FE capacitor including cross-sectionalviews and a 3D view, in accordance with some embodiments.

FIG. 4B illustrates a 3D view of a 1T1C FE bit-cell with the PL parallelto the BL, where the transistor is a planar transistor and where thecapacitor is a non-planar capacitor, where the BL is at a higher metallevel than the PL, in accordance with some embodiments.

FIG. 4C illustrates a 3D view of a 1T1C FE bit-cell with the PL parallelto the BL, where the transistor is a non-planar transistor and where thecapacitor is a non-planar capacitor, where the BL is at a lower metallevel than the PL, in accordance with some embodiments.

FIG. 4D illustrates a 3D view of a 1T1C FE bit-cell with the PL parallelto the BL, where the transistor is a non-planar transistor and where thecapacitor is a non-planar capacitor, where the BL is at a higher metallevel than the PL, in accordance with some embodiments.

FIG. 5A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes two transistors and one capacitor(2T1C) with a PL parallel to a BL, in accordance with some embodiments.

FIG. 5B illustrates an FE memory with word-line repeaters, whereinmemory arrays of the FE memory have 2T1C bit-cells with the PL parallelto the BL, in accordance with some embodiments.

FIG. 6A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes one transistor and multiplecapacitors (1TnC) with PLs parallel to a BL, where the correspondinglogic is to apply word-line boosting, in accordance with someembodiments.

FIG. 6B illustrates an FE memory with word-line repeaters, whereinmemory arrays of the FE memory have 1TnC bit-cells with the PL parallelto the BL, in accordance with some embodiments.

FIG. 6C illustrates a timing diagram for write operation for 1TnC FEmemory bit-cells with plate-lines parallel to the bit-line, where thewrite operation involves word-line boosting, in accordance with someembodiments.

FIG. 6D illustrates a timing diagram for read operation for 1TnC FEmemory bit-cells with plate-lines parallel to the bit-line, where theread operation involves word-line boosting, in accordance with someembodiments.

FIG. 7A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell is multi-element FE gain bit-cell with PLsparallel to a BL, where the corresponding logic is to apply word-lineboosting, in accordance with some embodiments.

FIG. 7B illustrates an FE memory with word-line repeaters, whereinmemory arrays of the FE memory have multi-element FE gain bit-cells withthe PL parallel to the BL, in accordance with some embodiments.

FIG. 7C illustrates a timing diagram for a first scheme for writeoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments.

FIG. 7D illustrates a timing diagram for a second scheme for writeoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments.

FIG. 7E illustrates a timing diagram for the first scheme read operationfor multi-element FE gain bit-cells with the PL parallel to the BL, inaccordance with some embodiments.

FIG. 7F illustrates a timing diagram for the second scheme readoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments.

FIG. 8A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes 1TnC bit-cells with PLs parallel toa BL, and with individual switches coupled to the capacitors on theplate-line side, where the corresponding logic is to apply word-lineboosting, in accordance with some embodiments.

FIG. 8B illustrates an FE memory with word-line repeaters, whereinmemory arrays of the FE memory 1TnC bit-cells of FIG. 8A, in accordancewith some embodiments.

FIG. 8C illustrates a timing diagram for write operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by a same signal, in accordance with some embodiments.

FIG. 8D illustrates a timing diagram for write operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by different signals, in accordance with some embodiments.

FIG. 8E illustrates a timing diagram for read operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by a same signal, in accordance with some embodiments.

FIG. 8F illustrates a timing diagram for write operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by different signals, in accordance with some embodiments.

FIG. 9A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes multi-element FE gain bit-cells withPLs parallel to a BL, and with individual switches coupled to thecapacitors on the plate-line side, where the corresponding logic is toapply word-line boosting, in accordance with some embodiments.

FIG. 9B illustrates an FE memory with word-line repeaters, whereinmemory arrays of the multi-element FE gain bit-cells of FIG. 9A, inaccordance with some embodiments.

FIG. 9C illustrates a timing diagram for write operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by a same signal, in accordance with someembodiments.

FIG. 9D illustrates a timing diagram for write operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by different signals, in accordance withsome embodiments.

FIG. 9E illustrates a timing diagram for read operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by a same signal, in accordance with someembodiments.

FIG. 9F illustrates a timing diagram for write operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by different signals, in accordance withsome embodiments.

FIG. 10A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes one transistor and an FE capacitorwith plate-line parallel to a word-line, where the corresponding logicis to apply word-line boosting, in accordance with some embodiments.

FIG. 10B illustrates an FE memory with word-line repeaters, whereinmemory arrays of the FE memory have 1T1C bit-cells with the plate-lineparallel to the word-line, in accordance with some embodiments.

FIG. 10C illustrates a timing diagram for write operation for 1T1C FEmemory bit-cells with plate-line parallel to the word-line, where thewrite operation involves word-line boosting, in accordance with someembodiments.

FIG. 10D illustrates a timing diagram for read operation for 1T1C FEmemory bit-cells with the plate-line parallel to the word-line, wherethe read operation involves word-line boosting, in accordance with someembodiments.

FIG. 11A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell is multi-element FE gain bit-cell withplate-lines parallel to a word-line, where the corresponding logic is toapply word-line boosting, in accordance with some embodiments.

FIG. 11B illustrates an apparatus having FE memory with word-linerepeaters, wherein memory arrays of the FE memory having multi-elementFE gain bit-cells with the plate-lines parallel to the word-line, inaccordance with some embodiments.

FIG. 11C illustrates a timing diagram for write operation formulti-element FE gain bit-cells with plate-line parallel to theword-line, where the write operation involves word-line boosting, inaccordance with some embodiments.

FIG. 11D illustrates a timing diagram for read operation formulti-element FE gain bit-cells with plate-line parallel to theword-line, where the read operation involves word-line boosting, inaccordance with some embodiments.

FIG. 12A illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a planar transistorand where the capacitor is a planar capacitor, where the bit-line is ata lower metal level than the plate-line, in accordance with someembodiments.

FIG. 12B illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a planar transistorand where the capacitor is a planar capacitor with partialencapsulation, where the bit-line is at a lower metal level than theplate-line, in accordance with some embodiments.

FIG. 12C illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a planar transistorand where the capacitor is a planar capacitor with full encapsulation,where the bit-line is at a lower metal level than the plate-line, inaccordance with some embodiments.

FIG. 12D illustrates a 3D view of 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a non-planartransistor and where the capacitor is a planar capacitor, where thebit-line is at a lower metal level than the plate-line, in accordancewith some embodiments.

FIG. 12E illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a non-planartransistor and where the capacitor is a planar capacitor with partialencapsulation, where the bit-line is at a lower metal level than theplate-line, in accordance with some embodiments.

FIG. 12F illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a non-planartransistor and where the capacitor is a planar capacitor with fullencapsulation, where the bit-line is at a lower metal level than theplate-line, in accordance with some embodiments.

FIG. 13A illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a planar transistorand where the capacitor is a non-planar capacitor, where the bit-line isat a higher metal level than the plate-line, in accordance with someembodiments.

FIG. 13B illustrates a 3D view of a 1T1C FE bit-cell with the plate-lineparallel to the word-line, where the transistor is a non-planartransistor and where the capacitor is a non-planar capacitor, where thebit-line is at a higher metal level than the plate-line, in accordancewith some embodiments.

FIG. 14A illustrates an apparatus comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell is 1TnC bit-cell with plate-lines parallel toa word-line, where the corresponding logic is to apply word-lineboosting, in accordance with some embodiments.

FIG. 14B illustrates an apparatus having FE memory with word-linerepeaters, wherein memory arrays of the FE memory having 1TnC bit-cellswith the plate-lines parallel to the word-line, in accordance with someembodiments.

FIG. 14C illustrates a timing diagram for write operation for 1TnCbit-cells with plate-line parallel to the word-line, where the writeoperation involves word-line boosting, in accordance with someembodiments.

FIG. 14D illustrates a timing diagram for read operation 1TnC bit-cellswith plate-line parallel to the word-line, where the read operationinvolves word-line boosting, in accordance with some embodiments.

FIG. 15 illustrates a high-level architecture of an artificialintelligence (AI) machine comprising a compute die stacked with a memorydie, wherein the compute die includes any one of the memoryarchitectures and associated read/write schemes, in accordance with someembodiments.

FIG. 16 illustrates an architecture of a computational block comprisinga compute die stacked with a memory die, wherein the compute dieincludes any one of the memory architectures and associated read/writescheme, in accordance with some embodiments.

FIG. 17 illustrates a system-on-chip (SOC) that uses any one of thememory architectures and associated read/write scheme, in accordancewith some embodiments.

FIG. 18 illustrates a cross-sectional view of bit-cells with stackedplanar non-linear polar material based capacitors, in accordance withsome embodiments.

FIG. 19 illustrates a cross-sectional view of bit-cells with stackednon-planar non-linear polar material based capacitors, in accordancewith some embodiments.

DETAILED DESCRIPTION

Memory bit-cells comprising ferroelectric material provide a new classof non-volatile memories. However, such memories suffer from chargedegradation over time, for example, during read operations. Suchmemories also suffer from charge disturbance when neighboring bit-cellcells are accessed. Such disturbance may be a function of routingconfiguration of plate-line(s), relative to bit-lines and word-lines.Further, leakage from transistors coupled to ferroelectric capacitor(s)may further degrade charge on a storage node connected to the capacitor.

Consider the case for an unselected memory bit-cell where word-line to agate of an n-type transistor of the bit-cell is at logic low. Continuingwith this example, when the plate-line coupled to the capacitor isparallel to a bit-line, which is coupled to a source terminal or a drainterminal of the n-type transistor, transitions from logic low to logichigh on the plate line results in a field across the ferroelectriccapacitor of this unselected memory bit-cell. This field causespolarization decay for a ferroelectric material in the ferroelectriccapacitor. The polarization decay causes the charge on the storage nodeto rise, which in turn weakens the disturb electric field across theferroelectric material of the unselected bit-cell. The weakened disturbelectric field causes the n-type transistor to leak, which in turncauses the disturb field to increase. As such, the unselected bit-cellsuffers from charge disturb when the plate-line is parallel to thebit-line. Depending on the charge stored in the ferroelectric capacitor,this disturb field can either disturb or reinforce the stored value inthe ferroelectric capacitor.

Parasitic capacitance (Cp) from the transistor and a dielectriccomponent (Cde) of the ferroelectric capacitor also results in acapacitor divider. This capacitor divider causes a voltage drop acrossthe ferroelectric capacitor of the unselected bit-cell. The voltage dropacross the unselected ferroelectric capacitor can be approximatelyone-third to one-fourth of a voltage on the plate-line. In one example,when the plate-line voltage is twice the coercive voltage (Vc) of theferroelectric capacitor, the disturb voltage can be two-thirds toone-half of the Vc for the unselected cell. Depending on the chargestored in the ferroelectric capacitor, this disturb voltage can eitherdisturb or reinforce the stored value in the ferroelectric capacitor.

To mitigate such charge disturbance, the memory bit-cells may berefreshed, in accordance with some embodiments. For example,ferroelectric based random access memory (FeRAM) may apply a refreshscheme to make sure the contents in its capacitor remain valid. Therefresh may be applied periodically or on an as needed basis. Forinstance, refresh may be applied every 1 second, or applied when asensor determines that the contents on a storage node may have beendisturbed. While various embodiments are described with reference to anFeRAM, the embodiments are applicable to other non-volatile memories(NVMs) such as magnetic random-access memory (MRAM), resistive RAM(ReRAM), ferroelectric RAM (FeRAM), paraelectric RAM (PeRAM),phase-change memory (PCM), etc.

In some embodiments, the NVM is integrated on a die which includescompute logic. In some embodiments, the NVM is a separate die which ispackaged in a single package with a compute die. In some embodiments,the NVM is on a different package than the compute die. Here, examplesof compute die include a die that is used for computations such as aninference logic, graphics processing unit (GPU), central processing unit(CPU), application specific integrated circuit (ASIC), digital signalprocessor (DSP), etc. In some embodiments, features of endurancemechanisms (e.g., randomizing mechanisms) are applicable to volatilememories such as static random-access memory (SRAM), and dynamicrandom-access memory (DRAM).

The endurance mechanisms (or refresh logic) of some embodiments includea wear leveling scheme that uses index rotation, outlier compensation tohandle weak bits, and random swap injection (which is an example of arandomizing mechanism) to mitigate wear out attacks. In someembodiments, an index rotation logic is provided, which rotates theaddresses throughout a memory bank to perform a wear leveling function.Index rotation logic ensures that memory requests are spread acrossmemory locations rather than a single memory location. In someembodiments, a randomizing mechanism is used to randomize a mapping ofan incoming address to an intermediate index. One example of arandomizing mechanism includes a random invertible bit matrix. Thisintermediate index is used by an index rotation logic to map to anactual physical index. In some embodiments, the rotation of gap words inthe memory bank is randomized. In some cases, malicious users (orattackers) may write programs that deliberately track the wear levelingscheme described herein. These attackers may attempt to alter a memoryreference pattern to continue to stress a single physical line even asthe wear leveling scheme assigns that physical line to differentaddresses. Some embodiments provide a facility to make tracking of thephysical lines difficult. This facility makes a random decision (e.g.,using an externally generated random number) to either swap or not eachtime a swap opportunity arises. Over time the randomness injected intothe swapping process makes tracking cache lines more difficult. In someembodiments, random invertible bit matrix enables random swap injectionwhich randomizes index rotation to obfuscate the mapping from addressesto rotated indexes. In some embodiments, bit repair logic is provided,which includes double error correcting, or triple error detecting errorcorrection code (ECC) to discover new bit errors and spare disable whicheliminates memory words with particularly high error rates.

Continuing with the example of a ferroelectric based memory bit-cell,the memory bit-cell is coupled to one or more plate-lines, a word-line,and a bit-line. The routing of the plate-line(s) relative to theword-line or the bit-line impacts the performance of the bit-cell. Someembodiments describe a read and write scheme (herein referred to as apulsing scheme) for memory arrays where plate-line(s) is/are parallel toa bit-line. Some embodiments describe a pulsing scheme for memory arrayswhere plate-line(s) is/are parallel to a word-line. The pulsing schemesdescribed with reference to various embodiments depend on a structure orconfiguration of a memory bit-cell. Some embodiments describe a pulsingscheme for a one-transistor, one-capacitor (1T1C) bit-cellconfiguration. Some embodiments describe a pulsing scheme for atwo-transistor, one-capacitor (2T1C) bit-cell configuration. Someembodiments describe a pulsing scheme for a one-transistor, n-capacitors(1TnC) bit-cell configuration. Some embodiments describe a pulsingscheme for multi-element FE gain bit-cell configuration.

In some embodiments, a memory is provided which comprises a capacitorincluding non-linear polar material. The capacitor may have a firstterminal coupled to a node (e.g., a storage node) and a second terminalcoupled to a plate-line. The capacitors can be a planar capacitor ornon-planar capacitor (also known as pillar capacitor). In variousembodiments, the memory comprises a transistor coupled to the node and abit-line (BL), wherein the transistor is controllable by a word-line(WL), and wherein the plate-line (PL) is parallel to the bit-line. Insome embodiments, the memory comprises a refresh circuitry (e.g.,wear-leveling logic) to refresh charge on the capacitor periodically orat a predetermined time. The refresh circuit can utilize one or more ofthe endurance mechanisms described herein. When the plate-line isparallel to the bit-line, a specific read and write scheme may be usedto reduce the disturb voltage for unselected bit-cells, in accordancewith some embodiments. In some embodiments, a transistor switch iscoupled to the plate-line to remove the effect of PL toggles on anunselected bit-line.

In some embodiments, the memory comprises one or more circuitries toboost the word-line above a voltage supply level (Vdd) during a writeoperation and a read operation. The boost level may range from 5% to 30%of Vdd, in some examples. In some embodiments, the one or morecircuitries generate a first pulse on the bit-line after the word-lineis boosted and before an end of the boost on the word-line during afirst write operation (e.g., Write 0). These one or more circuitries canbe circuitries on the periphery of the memory. In some embodiments, theone or more circuitries generate a second pulse on the plate-line afterthe word-line is boosted and before the end of the boost on theword-line during a second write operation (e.g., Write 1) different fromthe first write operation.

In some embodiments, the one or more circuitries force a first voltage(e.g., 0V) on the plate-line during the first write operation. In someembodiments, the one or more circuitries force the first voltage on thebit-line during the first write operation. In some embodiments, the oneor more circuitries initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation,wherein the one or more circuitries boost the word-line above thevoltage supply level during the read operation. In some embodiments, theone or more circuitries generate a third pulse on the plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation. The pulsing scheme of various embodimentsavoid high voltage on the node (storage node) when the plate-line isparallel to the bit-line. While the pulsing scheme is described for aone transistor, one capacitor (herein 1T1C), based memory bit-cell, thescheme is applicable to other memory bit cells such as 1TnC, 2T1C, 1TnC,and multi-element FE gain configurations as described herein. In someembodiments, the transistor is a low leakage transistor. For example,the transistor is a high-threshold transistor in a dual threshold CMOSprocess technology node. The lower leakage transistor limits theeffective field across the ferroelectric based capacitor by lowering theeffective field, and as such delays the process of refreshing thecapacitor. In some embodiments, by having the plate-line(s) parallel tothe bit-lines, the memory layout allows for introducing word-linedrivers or repeaters to drive signals on the word-lines, which runorthogonal to the plate-line(s) and the bit-lines.

Other ways to reduce the effect of the disturb charge when theplate-line is parallel to the bit-line is to lower the thickness (alongthe z-axis for a planar capacitor) of the ferroelectric material, inaccordance with some embodiments. Reducing the thickness may reduce arelative impact of a parasitic capacitance (Cp) on a storage or internalnode of the memory cell relative to a dielectric capacitance (Cdie).Here, the dielectric capacitance is of a dielectric component of theferroelectric based capacitor of the memory bit-cell. The thickness ofthe ferroelectric material of the ferroelectric based capacitor along az-axis can be in the range of 5 nm to 30 nm, in accordance with someembodiments.

In some embodiments, the effect of the disturb charge is mitigated byusing a higher dielectric constant for the ferroelectric material. Forexample, ferroelectric based capacitor of higher dielectric constant canhave a dielectric constant between 100 and 600. The higher dielectricconstant and/or lower film thickness reduces the effective field for anunselected bit-cell coupled to the same PL in proportion to Cp/(Cdie+Cp)as the dielectric capacitance component of the ferroelectric capacitorincreases relative to the parasitic component on the storage or internalnode.

In some embodiments, the disturb voltage is reduced by lowering theparasitics on the storage or internal node. Lowering the parasitics (Cp)improves the ratio Cp/Cdie+Cp) to lower the effective disturb field seenacross the ferroelectric capacitor for an unselected bit-cell. In someembodiments, replacing the 1T1C memory bit-cell topology with a 2T1Ctopology can isolate the plate-line signal visibility for the unselectedbit-cells as activity seen on the PL can be masked to other unselectedbit-cells by controlling a switch (a transistor) on the PL to be inoff-state. As such, the effect of the disturb voltage reduces. In someembodiments, the effect of the disturb charge is mitigated by changingthe read mechanism. For example, changing the pattern of read 1 relativeto read 0 periodically reduces the effect of the disturb charge. Assuch, read disturbances are averaged and thus reduced from their peakvalues.

In some embodiments, for a multi-element gain memory bit-cell, when theplate-line is parallel to the bit-line, read operation may result inreading all the memory bit-cells since the charge on the storage nodemay flip for all bit-cells. The charge on the storage node may flipbecause of excessive parasitic capacitance on the storage or internalnode which is shared by multiple ferroelectric capacitors of the samemulti-element gain memory bit-cell. Since the parasitic capacitance isgreater than the dielectric capacitance, the field is applied to all theferroelectric capacitors that are shared on the same plate-line, even ifthe bit-cell was unselected.

A multi-element FE gain memory bit-cell comprises a plurality offerroelectric capacitors, where an individual ferroelectric capacitor iscoupled to an individual plate-line. Two transistors are coupled to thestorage node, which is also coupled to the ferroelectric capacitors. Oneof the transistors is controlled by the word-line and coupled to thebit-line, while the other transistor is controlled by the voltage on thestorage node. This other transistor has a source terminal, or a drainterminal coupled to the bit-line. In some embodiments, the issue thatresults in reading all the memory bit-cells is resolved by introducingan individual transistor between an individual plate-line and anindividual ferroelectric capacitor. This individual transistor iscontrolled by an individual word-line. These individual transistors onthe plate-line ensure that the plate-line signal toggle is not seen byother bit-cells on the same column when the bit-cells share the samebit-line. In some embodiments, the area usage from the additionaltransistors on the individual plate-lines is mitigated by fabricatingthe additional transistors (also referred to as switches) in the backendof a die while the other two transistors of the bit-cell are fabricatedon the front-end of the die.

In some cases, the plate-line is parallel to the word-line. In thatcase, a write operation without appropriate signaling may inherentlymean writing the same value to each bit-cell. For example, writing avalue by controlling the plate-line, which is shared across all selectedbit-cells since the plate-line is parallel to the word-line, may resultin writing the same value to all the bit-cells. To control this effect,in some embodiments, the one or more circuitries carry out a differentpulsing scheme for read or write operations when the plate-line isparallel to the word-line. In some embodiments, the one or morecircuitries boost the word-line above a voltage supply level during awrite operation and a read operation. In some embodiments, the one ormore circuitries generates a first pulse on the bit-line after theword-line is boosted and before an end of the boost on the word-lineduring a first write operation (Write 1). In some embodiments, the oneor more circuitries generates a second pulse on the plate-line after theword-line is boosted and before the end of the boost on the word-lineduring a second write operation (e.g., Write 0) different from the firstwrite operation. In some embodiments, the one or more circuitriesgenerate a third pulse on the plate-line after the word-line is boostedand after the first pulse begins during the first write operation,wherein the third pulse ends about a time when the first pulse ends. Insome embodiments, in the case where the plate-line is parallel to theword-line, the memory comprises a refresh circuitry to refresh charge onthe capacitor periodically or at a predetermined time. The refreshcircuit can utilize one or more of the endurance mechanisms describedherein.

Referring back to the 1T1C example, where the plate-line is parallel tothe bit-line, in some embodiments, the one or more circuitries force afirst voltage (e.g., 0V) on the bit-line during the second writeoperation. In some embodiments, the one or more circuitries generates afourth pulse on the plate-line after the word-line is boosted, whereinthe fourth pulse ends before the end of the boost on the word-line. Insome embodiments, the one or more circuitries initially force a voltageon the bit-line and subsequently allow the bit-line to float during theread operation, wherein the one or more circuitries is to boost theword-line above the voltage supply level during the read operation. Insome embodiments, the one or more circuitries generates a fifth pulse onthe plate-line after the word-line is boosted and before an end of theboost on the word-line during the read operation, wherein the fifthpulse starts when the bit-line is allowed to float. In some embodiments,the one or more circuitries boost the word-line by about 0.3V above avoltage on the bit-line or the plate-line. In some embodiments, the oneor more circuitries boost the word-line by about 1.5× of a thresholdvoltage of the transistor (herein also referred to as a selecttransistor). In some embodiments, the transistor is a low leakagetransistor. In some embodiments, by having the plate-line(s) parallel tothe word-lines, the memory layout allows for introducing plate-linedrivers or repeaters to drive signals on the plate-lines, which runorthogonal to the bit-lines. In addition to plate-line repeaters, thememory layout allows for introducing word-line drivers or repeaters todrive signals on the word-lines, which run orthogonal to the bit-lines.

In a multi-element FE gain memory bit-cell configuration, multiplecapacitors are coupled to the node (storage node) and two transistors,where one transistor (e.g., the select transistor) is controllable byword-line and the other transistor is a gain element. In someembodiments, a pulsing scheme is described which avoids writing the samevalue to all multi-element FE gain memory bit-cells. In someembodiments, the memory, with multi-element FE gain memory bit-cell,comprises a refresh circuitry to refresh charge on the capacitorperiodically or at a predetermined time. The refresh circuit can utilizeone or more of the endurance mechanisms described herein. When theplate-line is parallel to the bit-line, column multiplexing is enabledwhich lowers the number of sense amplifiers needed to sense the valuesstored in the memory bit-cells, in accordance with some embodiments. Assuch, lower periphery area overhead is achieved. In the case where theplate-line is parallel to the bit-line, a plate-line driver switches onememory bit-cell (and thus one ferroelectric capacitor). As such, theplate-line driver size can be reduced, which improves power and area, inaccordance with some embodiments. In the case where the plate-line isparallel to the word-line, column multiplexing may be relativelychallenging.

However, in the case where the plate-line is parallel to the word-line,the energy cost on the plate-line is lower than that in the case wherethe plate-line is parallel to the bit-line. This is because parasiticcapacitance on the plate-line is amortized over multiple bit-cells, asopposed to the case where the plate-line is parallel to the bit-linewhere multiple plate-lines are toggled. Likewise, in the case where theplate-line is parallel to the word-line, the disturb effects are lowerthan that in the case where the plate-line is parallel to the bit-line.This is because merely the bits that are intended to be read or writtenare the ones that get exposed to the plate-line, word-line, and bit-linesignals. A disturb effect generally refers to an unintentionalapplication of field on the ferroelectric capacitor(s) coupled tounselected bit-cells during read or write operations of adjacentbit-cells on the same row or column. Such a disturb effect can cause theferroelectric capacitors of the unselected bit-cells to lose their polarstate slowly over time.

When the bit-cells that are getting programmed to (e.g., eitherread/write) are the bit-cells that see the voltages on the plate-lineand the word-line directly, the transistor on the bit-line masks theunselected bits, unlike the case when the plate-line is parallel to thebit-line where the unselected bit-cells within the 1T1C bit-cell seeactivities on the plate-line without any transistor masking the signal.As discussed herein, the pulsing schemes for the various memory bit-cellconfigurations reduces disturb effect and allows for realization of areliable non-volatile memory. Other technical effects will be evidentfrom the various embodiments and figures.

In the following description, numerous details are discussed to providea more thorough explanation of embodiments of the present disclosure. Itwill be apparent, however, to one skilled in the art, that embodimentsof the present disclosure may be practiced without these specificdetails. In other instances, well-known structures and devices are shownin block diagram form, rather than in detail, to avoid obscuringembodiments of the present disclosure.

Note that in the corresponding drawings of the embodiments, signals arerepresented with lines. Some lines may be thicker, to indicate moreconstituent signal paths, and/or have arrows at one or more ends, toindicate primary information flow direction. Such indications are notintended to be limiting. Rather, the lines are used in connection withone or more exemplary embodiments to facilitate easier understanding ofa circuit or a logical unit. Any represented signal, as dictated bydesign needs or preferences, may actually comprise one or more signalsthat may travel in either direction, and may be implemented with anysuitable type of signal scheme.

It is pointed out that those elements of the figures having the samereference numbers (or names) as the elements of any other figure canoperate or function in any manner like that described but are notlimited to such.

FIG. 1 illustrates a set of plots 100 and 120 showing behavior of aferroelectric capacitor, a paraelectric capacitor, and a linearcapacitor. Plot 100 compares the transfer function for a linearcapacitor, a paraelectric (PE) capacitor (a non-linear capacitor) and aferroelectric (FE) capacitor (a non-linear capacitor). Here, x-axis isinput voltage or voltage across the capacitor, while the y-axis is thecharge on the capacitor. The ferroelectric material can be any suitablelow voltage FE material that allows the FE material to switch its stateby a low voltage (e.g., 100 mV). Threshold in the FE material has ahighly non-linear transfer function in the polarization vs. voltageresponse. The threshold is related to: a) non-linearity of switchingtransfer function; and b) the squareness of the FE switching. Thenon-linearity of the switching transfer function is the width of thederivative of the polarization vs. voltage plot. The squareness isdefined by the ratio of the remnant polarization to the saturationpolarization, perfect squareness will show a value of 1. The squarenessof the FE switching can be suitably manipulated with chemicalsubstitution. For example, in PbTiO3 a P-E (polarization-electric field)square loop can be modified by La or Nb substitution to create anS-shaped loop. The shape can be systematically tuned to ultimately yielda non-linear dielectric. The squareness of the FE switching can also bechanged by the granularity of an FE layer. A perfectly epitaxial, singlecrystalline FE layer will show higher squareness (e.g., ratio is closerto 1) compared to a polycrystalline FE. This perfect epitaxial can beaccomplished using lattice matched bottom and top electrodes. In oneexample, BiFeO (BFO) can be epitaxially synthesized using a latticematched SrRuO3 bottom electrode yielding P-E loops that are square.Progressive doping with La will reduce the squareness.

Plot 120 shows the charge and voltage relationship for a ferroelectriccapacitor. A capacitor with ferroelectric material (also referred to asa FEC) is a non-linear capacitor with its potential V_(F)(Q_(F)) as acubic function of its charge. Plot 120 illustrates characteristics of anFEC. Plot 120 is a charge-voltage (Q-V) plot for a block ofPb(Zr_(0.5)Ti_(0.5))O₃ of area (100 nm)² and thickness 20 nm(nanometer). Plot 120 shows local extrema at +/−V_(o) indicated by thedashed lines. Here, the term V_(c) is the coercive voltage. In applyinga potential V across the FEC, its charge can be unambiguously determinedonly for |V|>V_(o). Otherwise, the charge of the FEC is subject tohysteresis effects.

FIG. 2A illustrates apparatus 200 comprising memory and correspondinglogic, wherein the memory comprises ferroelectric (FE) memory bit-cell,where an individual memory bit-cell includes one transistor and onecapacitor (1T1C) with plate-line parallel to a bit-line, where thecorresponding logic is to apply word-line boosting, in accordance withsome embodiments. Apparatus 200 comprises M×N memory array 201 ofbit-cells, logic circuitry 202 for address decoding, and logic circuitry203 for sense amplifier, write drivers, and plate-line (PL) drivers.Plate-lines PL0, PL1 through PLN are parallel to bit-lines BL0, BL1through BLN, while word-lines WL0, WL1, through WLM are orthogonal tothe plate-lines and the bit-lines, where ‘N’ is a number greater than 1.

In some embodiments, bit-cell 201 _(0,0) comprises a word-line (WL)coupled to WL0, a plate-line (PL) coupled to PL0, and a bit-line (BL)coupled to BL. In some embodiments, bit-cell 201 _(0,0) comprises ann-type transistor MN₁, and FE capacitive structure Cfe₁. The gates oftransistors MN₁ of bit-cells in a row are coupled to a common WL. Invarious embodiments, one terminal of the FE capacitive structure Cfe₁ iscoupled to a PL. The second terminal of the FE capacitive structure Cfe1is coupled to a source terminal or a drain terminal (also referred to asstorage node sn1) of the n-type transistor MN₁. In various embodiments,bit-line (BL) is coupled to the source or drain terminal of transistorMN₁. In some embodiments, BL parasitic capacitor Cbl₁ is coupled to thesource or drain terminal of transistor MN₁ and to a reference node(e.g., ground) such that the FE capacitor is not coupled to the samesource or drain terminal. In some embodiments, the PL is parallel to theBL and orthogonal to the word-line (WL). In some embodiments, the FEcapacitor is a planar capacitor. In some embodiments, the FE capacitoris a pillar or non-planar capacitor.

Logic circuitry 202 comprises address decoders for selecting a row ofbit-cells and/or a particular bit-cell from M×N array 201, where M and Nare integers of same or different values. In some embodiments, logiccircuitry 202 includes word-line drivers. In some embodiments, logiccircuitry 203 comprises sense-amplifiers (SAs) for reading the valuesfrom the selected bit-cell. Since the PL is parallel to the BL, in someembodiments, PL drivers and BL drivers are part of logic circuitry 203.In other embodiments, PL drivers and BL drivers may be placed acrosslogic circuitry 203 on the other side of memory array 201. In variousembodiments, write drivers are used to write a particular value to aselected bit-cell. Here, a schematic of FE bit-cell 201 _(0,0) isillustrated. The same embodiments apply to other bit-cells of the M×Narray. In this example, a one-transistor one-capacitor (1T1C) bit-cellis shown, but the embodiments are applicable to 2T1C, 1TnC bit-cell andmulti-element FE gain bit-cell as described herein. As the PL isparallel to the bit-line, the WL drivers can be placed orthogonal to theregion where the plate-line drivers and bit-line drivers are placed, inaccordance with some embodiments. In some embodiments, WL repeaters 205are added to buffer the word-line signals along different memory arrays.In some embodiments, apparatus 200 comprises wear-leveling logic 206(also referred to as refresh logic) to refresh the contents of thememory bit-cells periodically or on a need-by-need basis.

FIG. 2B illustrates a high-level endurance enhancement architecture 220(e.g., wear-leveling logic 206) for the FE memory, in accordance withsome embodiments. High-level rchitectureendurance enhancementarchitecture 220 comprises memory array 201 and wear-leveling logic 206.In various embodiments, memory array 201 is memory with non-linear polarmaterial. For example, memory array 201 includes bit-cells that compriseat least one transistor and at least one capacitor coupled to it, wherethe capacitor has non-linear polar material. Examples of non-linearmaterial include ferroelectric (FE) material, paraelectric (PE)material, and non-linear dielectric material.

In various embodiments, the FE material can be any suitable low voltageFE material that allows the FE material to switch its state by a lowvoltage (e.g., 100 mV). Threshold in FE material has a highly non-lineartransfer function in the polarization vs. voltage response. Thethreshold is related to: a) non-linearity of switching transferfunction; and b) the squareness of the FE switching. The non-linearityof the switching transfer function is the width of the derivative of thepolarization vs. voltage plot. The squareness is defined by the ratio ofthe remnant polarization to the saturation polarization; perfectsquareness will show a value of 1.

The squareness of the FE switching can be suitably manipulated withchemical substitution. For example, in PbTiO3 a P-E(polarization-electric field) square loop can be modified by La or Nbsubstitution to create an S-shaped loop. The shape can be systematicallytuned to ultimately yield a non-linear dielectric. The squareness of theFE switching can also be changed by the granularity of an FE layer. Aperfectly epitaxial, single crystalline FE layer will show highersquareness (e.g., ratio is closer to 1) compared to a polycrystallineFE. This perfect epitaxial can be accomplished using lattice matchedbottom and top electrodes. In one example, BiFeO (BFO) can beepitaxially synthesized using a lattice matched SrRuO3 bottom electrodeyielding P-E loops that are square. Progressive doping with La willreduce the squareness.

In some embodiments, the FE material comprises a perovskite of the typeABO₃, where ‘A’ and ‘B’ are two cations of different sizes, and ‘O’ isoxygen which is an anion that bonds to both the cations. Generally, thesize of atoms of A is larger than the size of B atoms. In someembodiments, the perovskite can be doped (e.g., by La or Lanthanides).

In some embodiments, the FE material is perovskite, which includes oneor more of: La, Sr, Co, Sr, Ru, Y, Ba, Cu, Bi, Ca, and Ni. For example,metallic perovskites such as: (La,Sr)CoO₃, SrRuO₃, (La,Sr)MnO₃,YBa₂Cu₃O₇, Bi₂Sr₂CaCu₂O₈, LaNiO₃, etc. may be used for FE material.Perovskites can be suitably doped to achieve a spontaneous distortion ina range of 0.3 to 2%. For example, for chemically substituted leadtitanate such as Zr in Ti site; La, Nb in Ti site, the concentration ofthese substitutes is such that it achieves spontaneous distortion in therange of 0.3-2%. For chemically substituted BiFeO3, BrCrO3, BuCoO3 classof materials, La or rate earth substitution into the Bi site can tunethe spontaneous distortion. In some embodiments, the FE material iscontacted with a conductive metal oxide that includes one of theconducting perovskite metallic oxides exemplified by: La—Sr—CoO3,SrRuO3, La—Sr—MnO3, YBa2Cu3O7, Bi2Sr2CaCu2O8, and LaNiO3. In someembodiments, perovskite includes one of: BaTiO3, PbTiO3, KNbO3, orNaTaO3.

In some embodiments, the FE material comprises a stack of layersincluding low voltage FE material between (or sandwiched between)conductive oxides. In various embodiments, when FE material is aperovskite, the conductive oxides are of the type AA′BB′O₃. A′ is adopant for atomic site A, it can be an element from the Lanthanidesseries. B′ is a dopant for atomic site B, it can be an element from thetransition metal elements, especially Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu,Zn. A′ may have the same valency of site A, with a differentferroelectric polarizability. In various embodiments, when metallicperovskite is used for the FE material, conductive oxides can includeone or more of: IrO₂, RuO₂, PdO₂, OsO₂, or ReO₃. In some embodiments,the perovskite is doped with La or Lanthanides. In some embodiments,thin layer (e.g., approximately 10 nm) perovskite template conductorssuch as SrRuO3 coated on top of IrO2, RuO2, PdO2, PtO2, which have anon-perovskite structure but higher conductivity to provide a seed ortemplate for the growth of pure perovskite ferroelectric at lowtemperatures, are used as conductive oxides.

In some embodiments, the ferroelectric materials are doped withs-orbital material (e.g., materials for first period, second period, andionic third and fourth periods). In some embodiments, f-orbitalmaterials (e.g., lanthanides) are doped to the ferroelectric material tomake paraelectric material. Examples of room temperature paraelectricmaterials include: SrTiO3, Ba(x)Sr(y)TiO3 (where x is −0.05, and y is0.95), HfZrO2, Hf—Si—O, La-substituted PbTiO3, PMN-PT based relaxorferroelectrics.

In some embodiments, the FE material comprises one or more of: Hafnium(Hf), Zirconium (Zr), Aluminum (Al), Silicon (Si), their oxides or theiralloyed oxides. In some embodiments, FE material includes one or moreof: Al(1-x)Sc(x)N, Ga(1-x)Sc(x)N, Al(1-x)Y(x)N or Al(1-x-y)Mg(x)Nb(y)N,y doped HfO2, where x includes one of: Al, Ca, Ce, Dy, Er, Gd, Ge, La,Sc, Si, Sr, Sn, or Y, wherein ‘x’ is a fraction. In some embodiments, FEmaterial includes one or more of: Bismuth ferrite (BFO), lead zirconatetitanate (PZT), BFO with doping material, or PZT with doping material,wherein the doping material is one of Nb or La; and relaxorferroelectrics such as PMN-PT.

In some embodiments, the FE material includes Bismuth ferrite (BFO), BFOwith a doping material where in the doping material is one of Lanthanum,or any element from the lanthanide series of the periodic table. In someembodiments, FE material includes lead zirconium titanate (PZT), or PZTwith a doping material, wherein the doping material is one of La, Nb. Insome embodiments, FE material includes a relaxor ferro-electric, whichincludes one of lead magnesium niobate (PMN), lead magnesiumniobate-lead titanate (PMN-PT), lead lanthanum zirconate titanate(PLZT), lead scandium niobate (PSN), Barium Titanium-Bismuth ZincNiobium Tantalum (BT-BZNT), Barium Titanium-Barium Strontium Titanium(BT-BST).

In some embodiments, the FE material includes Hafnium oxides of theform, Hf1-x Ex Oy where E can be Al, Ca, Ce, Dy, er, Gd, Ge, La, Sc, Si,Sr, Sn, or Y. In some embodiments, the FE material includes Niobate typecompounds LiNbO3, LiTaO3, Lithium iron Tantalum Oxyfluoride, BariumStrontium Niobate, Sodium Barium Niobate, or Potassium strontiumniobate.

In some embodiments, the FE material comprises multiple layers. Forexample, alternating layers of [Bi2O2]2+, and pseudo-perovskite blocks(Bi4Ti3O12 and related Aurivillius phases), with perovskite layers thatare ‘n’ number of octahedral layers in thickness can be used. In someembodiments, FE material comprises organic material. For example,Polyvinylidene fluoride or polyvinylidene difluoride (PVDF).

In some embodiments, the FE material comprises hexagonal ferroelectricsof the type h-RMnO3, where R is a rare earth element viz. cerium (Ce),dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), holmium(Ho), lanthanum (La), lutetium (Lu), neodymium (Nd), praseodymium (Pr),promethium (Pm), samarium (Sm), scandium (Sc), terbium (Tb), thulium(Tm), ytterbium (Yb), and yttrium (Y). The ferroelectric phase ischaracterized by a buckling of the layered MnO5 polyhedra, accompaniedby displacements of the Y ions, which lead to a net electricpolarization. In some embodiments, hexagonal FE includes one of: YMnO3or LuFeO3. In various embodiments, when FE material comprises hexagonalferroelectrics, the conductive oxides are of A2O3 (e.g., In2O3, Fe2O3)and ABO3 type, where ‘A’ is a rare earth element and B is Mn.

In some embodiments, FE material comprises improper FE material. Animproper ferroelectric is a ferroelectric where the primary orderparameter is an order mechanism such as strain or buckling of the atomicorder. Examples of improper FE material are LuFeO3 class of materials orsuper lattice of ferroelectric and paraelectric materials PbTiO3 (PTO)and SnTiO3 (STO), respectively, and LaAlO3 (LAO) and STO, respectively.For example, a super lattice of [PTO/STO]n or [LAO/STO]n, where ‘n’ isbetween 1 and 100. While various embodiments here are described withreference to ferroelectric material for storing the charge state, theembodiments are also applicable for paraelectric material. For example,the capacitor of various embodiments can be formed using paraelectricmaterial instead of ferroelectric material.

While various embodiments here are described with reference toferroelectric material for storing the charge state, the embodiments arealso applicable for paraelectric material. For example, non-linearparaelectric material of various embodiments can be formed usingparaelectric material instead of ferroelectric material. In someembodiments, paraelectric material includes one of: SrTiO3,Ba(x)Sr(y)TiO3 (where x is −0.5, and y is 0.95), HfZrO2, Hf—Si—O,La-substituted PbTiO3, or PMN-PT based relaxor ferroelectrics.

In some embodiments, FE memory array 201 includes a plurality of memorybanks (e.g., 223-1 through 223-N, where ‘N’ is a number). Each memorybank (e.g., 223-1) includes a plurality of memory words (e.g., memoryword 227). Each memory word includes a plurality of memory bit-cells.For the sake of simplicity, other memory components are not shown suchas write drivers, column multiplexers, sense-amplifiers, etc.

In various embodiments, wear-leveling logic 206 comprises endurancehardware and/or software to provide memory endurance to memory array201. In general, memory endurance is needed to ensure write and/or readoperations from memory array 201 are reliable. Write endurance is anumber of programs and erase cycles that, when applied to a memoryblock, bank, or word before the memory block, bank, or word, becomesunreliable. The endurance mechanisms of some embodiments include a wearleveling scheme that uses index rotation, outlier compensation to handleweak bits, and random swap injection to mitigate wear out attacks. Forthe sake of simplicity, memory banks are generally referred by theirreference 223 instead of a particular memory bank reference (e.g.,223-1, 223-2, etc.). Embodiments described to the general reference areapplicable to an individual particular reference. For example,description of memory bank 223 is applicable for memory banks 223-1,223-2, through 223-N.

In some embodiments, wear-leveling logic 206 (also referred to ascontroller or refresh logic) comprises random invertible bit matrix 206a, index rotation logic 206 b, and bit repair logic 206 c. In someembodiments, index rotation logic 206 b enables random swap injectionwhich randomizes index rotation to obfuscate the mapping from addressesto rotated indexes. In some embodiments, index rotation logic 206 brandomizes the rotation of gap words in memory bank 223. In some cases,malicious users (or attackers) may write programs that deliberatelytrack the wear leveling scheme described herein. These attackers mayattempt to alter a memory reference pattern to continue to stress asingle physical line even as the wear leveling scheme assigns thatphysical line to different addresses. Some embodiments provide afacility to make tracking of the physical lines difficult. This facilitymakes a random decision (e.g., using an externally generated randomnumber) to either swap or not each time a swap opportunity arises. Overtime the randomness injected into the swapping process makes trackingcache lines more difficult.

In some embodiments, index rotation logic 206 b is used for implementingthe wear leveling scheme. In some embodiments, index rotation logic 206b rotates the addresses throughout memory bank 223 to perform a wearleveling function. In various embodiments, index rotation logic 206 bensures that memory requests are spread across memory locations ratherthan a single memory location.

In some embodiments, bit repair logic 206 c includes double errorcorrecting, or triple error detecting error correction code (ECC) todiscover new bit errors and spare disable which eliminate memory wordswith particularly high error rates. Spare disable involves having abuffer of spare cache lines. When cache lines are particularlyunreliable, spare disable can swap out unreliable cache lines for thereliable spares. In some embodiments, the spares may be implemented witha memory technology other than FE memory such as static random-accessmemory (SRAM). In various embodiments, bit repair logic 206 c addressesthe problem of weak memory bits. In some embodiments, each cache line ormemory word 227 in memory bank 223 includes a valid bit. The valid bitindicates whether the data associated with that line/word is stored inthe memory or the redundant word array. The redundant word arraycomprises spares that can be used to compensate for defective words inmemory. When accessing memory, wear-leveling logic 206 checks the validbit, if the valid bit is set then the data is stored in the redundantmemory rather than the memory array or bank 223. In various embodiments,ECC is used to identify and/or correct bit errors in both the memoryarray and the redundant memory. As the ECC discovers bit errors,additional lines may be marked valid and the data stored in theredundant memory location rather than the memory. The various endurancemechanisms discussed herein can be used in any combination or order.Some memory products may select one or more of the endurance mechanismsinstead of all three discussed herein. Some memory products may applyall three endurance mechanisms to achieve most endurance for FE memoryarray 201. These endurance mechanisms are applied to FE memory array 201to maximize usage of such memory.

FIG. 2C illustrates flowchart 230 of memory endurance for the FE memory,in accordance with some embodiments. While the blocks in flowchart 230are illustrated in a particular order, the order can be modified. Forexample, some blocks may be performed before others based on whetherread or write operations are being performed. As described herein, thevarious blocks can be implemented in hardware, software, or acombination of them.

At block 231, wear-leveling logic 206 sends a memory request to memoryarray 201. This request may be a read request or a write request. If itis a write request, wear-leveling logic 206 applies the wear levelingscheme at block 232. In some embodiments, the wear leveling scheme islinear in that a gap word or gap cache line is swapped with an adjacentword or cache line. In some embodiments, wear leveling is dithered asindicated by block 232 a. In one such embodiment, the index or pointerto gap word or gap cache line is used to swap the gap word or gap cacheline with either an adjacent cell with one higher index or address orwith an adjacent cell with one lower index or address. As such, wearleveling is dithered.

In some embodiments, wear leveling is randomized In one such embodiment,a random index is generated at block 232 b. This random index is thenused to swap the gap word or gap cache line with an adjacent or anon-adjacent word or cache line. In some embodiments, the random indexis dithered. This dithered random index is then used for wear leveling.

In some embodiments, if the memory request is a read access (asindicated by block 235), outlier compensation is applied as indicated byblock 236. At block 236, wear-leveling logic 206 addresses the problemof weak memory bits by checking a valid bit for the memory word beingaddressed or accessed. The valid bit indicates whether the dataassociated with that line or word is stored in the memory or theredundant word array. The redundant word array comprises spares that canbe used to compensate for defective words in memory. When accessingmemory, wear-leveling logic 206 checks the valid bit, if the valid bitis set then the data is stored in the redundant memory rather than thememory array or bank 223. In various embodiments, ECC is used toidentify and/or correct bit errors in both the memory array and theredundant memory. As the ECC discovers bit errors, additional lines maybe marked valid and the data stored in the redundant memory locationrather than the memory. After ECC is applied, the requested data isprovided to wear-leveling logic 206 as indicated by block 237. Thememory endurance for non-linear polar material based memory is enhancedby the endurance mechanisms of various embodiments. This allows moreread and writes to memory before any memory block, bank, or word becomesunreliable.

FIG. 2D illustrates apparatus 240 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory have 1T1C bit-cellswith the plate-line parallel to the bit-line, in accordance with someembodiments. Apparatus 240 illustrates two instances of apparatus 200.The two instances include first memory array 201-1, logic circuitry202-1 having first address decoder and/or WL driver, and logic circuitry203-1 having first sense amplifier, BL driver, PL driver; and WLrepeaters 205-1; and second memory array 201-2, logic circuitry 202-2having address decoder and/or WL driver, and logic circuitry 203-2having first sense amplifier, BL driver, PL driver; and WL repeaters205-2. In some embodiments, an individual instance of apparatus 200includes a corresponding wear-leveling logic 206 (e.g., wear-levelinglogic 206-1 and wear-leveling logic 206-2). In some embodiments,wear-leveling logic 206 is shared by multiple instances of apparatus200. In some embodiments, when the pulsing scheme described herein iscombined with the refresh function by wear-leveling logic 206-1 andwear-leveling logic 206-2, disturb issues on unselected bit-cells aremitigated. While two memory arrays are shown (e.g., array 201-1 and201-2), any number of arrays may be part of apparatus 240. With PLparallel to the BL and orthogonal to the WL, WL repeaters 205-1, 205-2,etc. are added to improve the driving strength of the word-line signals.In some embodiments, WL repeaters 205-1 and 205-2 operate on a higherpower supply level (e.g., Vdd+Vboost) to implement WL boosting.

Timing diagrams of various embodiments here show timepoints t1, t2, t3,t4, and onwards. These time points are shown as equally spaced. However,the time points can be separated by any time period.

FIG. 2E illustrates timing diagram 250 for write operation for 1T1C FEmemory bit-cells, where the write operation involves word-line boosting,in accordance with some embodiments. In this case, PL is parallel to theBL. Depending on whether logic 1 (Write 1) or logic 0 (Write 0) is beingwritten to the capacitor with non-linear polar material, BL or PL forthat bit-cell is asserted from 0V to Vdd (power supply level). Invarious embodiments, write operation begins when WL is asserted andboosted above Vdd. The boost level is Vboost which may be 10% to 50% ofVdd. In one example, Vboost is about 1× to 1.5× of a threshold voltage(Vt) of the select transistor MN₁ of the 1T1C bit-cell (e.g., 201_(0,0)).

Since, the select transistor MN₁ in these configurations is an n-channeldevice, it is good at passing the 0V and signals closer to it. Thesignal applied through the BL however, when it is at Vdd, may not passthrough the transistor MN₁ in completeness. As such, there is a Vt dropacross the select transistor MN₁ if the WL is driven to Vdd. To help getthe full range of signaling across the FE capacitor Cfe1, WL-boostinghelps negate the Vt drop across the select transistor MN₁ such that BLwhen driven to Vdd, internal node sn1 will also see Vdd, as opposed toVdd−Vt.

When a particular bit-cell (e.g., 201 _(0,0)) is being written to, theWL for unselected bit-cells (e.g., on WL0 through WLm) remains at 0V.Same is done for unselected BLy and PLy by column multiplexers. In thisexample, the selected WL is WL1 and selected BL and PL are BLx and PLx.In various embodiments, the BL and PL are asserted and de-assertedwithin a pulse width of the boosted WL. In some embodiments, the voltageswing for BL and PL is 0V to Vdd. In some embodiments, BL or PL pulse isgenerated after a predetermined or programmable time from when WL booststarts.

FIG. 2F illustrates timing diagram 260 for read operation for 1T1C FEmemory bit-cells, where the read operation involves word-line boosting,in accordance with some embodiments. In this case, PL is parallel to theBL. In some embodiments, read operation begins by asserting the selectedWL. In some embodiments, the selected WL is boosted for read operation.WL is boosted above Vdd to Vdd+Vboost level. In some embodiments, awriteback scheme is implemented after the read operation to restore thedata value stored in the selected bit-cell due to the destructive natureof the read operation. In one such embodiment, the data which is read isalso written back in the writeback time window after the read timewindow. In some embodiments, PL is asserted for the bit-cell which isbeing read. PL is asserted for a time period long enough for the senseamplifier to sense the value stored on the storage node coupled to thecapacitor. In various embodiments, sense amplifier enable signal (SAE)is asserted within the pulse width of the PL.

In some embodiments, to read data from the storage node sn1, BL is firstset or forced to zero volts and then allowed to float (e.g., BL drivergoes into high impedance state Z (HiZ)). In some embodiments, BL isprecharged to a certain voltage or a programmable voltage so when the WLis selected, in conjunction with the PL voltage, a field is createdacross the FE capacitor Cfe1. Thereafter, the BL driver is configured inhigh impedance state, the selected BL is floated, which allows the senseamplifier to sense the voltage on the storage node via the BL. In someembodiments, the sense amplifier is configured to sense the voltage onthe BL by comparing it to one or more thresholds. In some embodiments,when the BL charges to a first voltage level, a logic 0 is read (Read0).In some embodiments, when the BL charges to a second voltage level(higher than the first voltage level), a logic 1 is read (Read1). Insome embodiments, after the sense amplifier is disabled (SAE is set to0), the voltage on the selected BL is forced to zero volts. In someembodiments, after the selected BL is forced to 0V, the write backprocess begins.

In the write back process, the selected bit-cell BL (e.g., BLx) ischarged to Vdd or set to 0V depending upon whether a logic 1 or a logic0 is written back to the selected bit-cell. The value written back tothe bit-cell is the same value that the sense amplifier detects whenreading the voltage on the BL. The write back mechanism is like thewrite operation described with reference to FIG. 2E. In variousembodiments, the WL for the unselected bit-cells is set to 0V (e.g.,WL0, WL2, . . . WLm is set to 0 when WL1 is selected). In variousembodiments, the BL for the unselected bit-cells (e.g., BLy) is set to0V during read and writeback operations. In some embodiments, the PL forthe unselected bit-cell (e.g., PLy) is set to 0V during read andwriteback operations. In some embodiments, the WLs for the unselectedbit-cell (e.g., WL0, WL2, . . . WLm) is set to 0V during read andwriteback operations.

FIG. 3A illustrates a three-dimensional (3D) view of a 1T1C FE bit-cell300 with the plate-line parallel to the bit-line, where the transistoris a planar transistor and where the capacitor is a planar capacitor, inaccordance with some embodiments. In some embodiments, memory bit-cell300 includes a planar transistor MN having substrate 301, source region302, drain region 303, channel region 304, a gate comprising gatedielectric 305, gate spacers 306 a and 306 b; gate metal 307, sourcecontact 308 a, and drain contact 308 b. In some embodiments, substrate301 includes a suitable semiconductor material such as single crystalsilicon, polycrystalline silicon or silicon on insulator (SOI). In someembodiments, substrate 301 includes other semiconductor materials suchas: Si, Ge, SiGe, or a suitable group III-V or group III-N compound. Insome embodiments, substrate 301 may also include semiconductormaterials, metals, dopants, and other materials commonly found insemiconductor substrates.

In some embodiments, source region 302 and drain region 303 are formedwithin substrate 301 adjacent to the gate stack of the transistor. Invarious embodiments, source region 302 and drain region 303 aregenerally formed using either an etching/deposition process or animplantation/diffusion process. In some embodiments, in the etching anddeposition process, substrate 301 may first be etched to form recessesat the locations of the source region 302 and drain region 303. Anepitaxial deposition process may then be carried out to fill therecesses with material that is used to fabricate the source region 302and drain region 303. In the implantation/diffusion process, dopantssuch as boron, aluminum, antimony, phosphorous, or arsenic may beion-implanted into the substrate to form the source region 302 and drainregion 303. An annealing process that activates the dopants and causesthem to diffuse further into substrate 301 typically theion-implantation process, in accordance with some embodiments. In someembodiments, one or more layers of metal and/or metal alloys are used toform source region 302 and drain region 303. In some embodiments, sourceregion 302 and drain region 303 are formed using one or more alternatesemiconductor materials such as germanium or a suitable group III-Vcompound. In some embodiments, source region 302 and drain region 303are fabricated using a silicon alloy such as silicon germanium orsilicon carbide. In some embodiments, the epitaxially deposited siliconalloy is doped in-situ with dopants such as boron, arsenic, orphosphorous. In some embodiments, semiconductor material for channelregion 304 may have the same material as substrate 301, in accordancewith some embodiments. In some embodiments, channel region 304 includesone of: Si, SiGe, Ge, or GaAs.

In some embodiments, gate dielectric 305 may include one layer or astack of layers. The one or more layers may include high-k dielectricmaterial, silicon oxide, and/or silicon dioxide (SiO₂). The high-kdielectric material may include elements such as zinc, niobium,scandium, lean yttrium, hafnium, silicon, strontium, oxygen, barium,titanium, zirconium, tantalum, aluminum, and lanthanum. Examples ofhigh-k materials that may be used in the gate dielectric layer includelead zinc niobate, hafnium oxide, lead scandium tantalum oxide, hafniumsilicon oxide, yttrium oxide, aluminum oxide, lanthanum oxide, bariumstrontium titanium oxide, lanthanum aluminum oxide, titanium oxide,zirconium oxide, tantalum oxide, and zirconium silicon oxide. In someembodiments, when a high-k material is used, an annealing process isused on the gate dielectric 305 to improve its quality.

In some embodiments, a pair of spacer layers (sidewall spacers) 306 a/bare formed on opposing sides of the gate stack that bracket the gatestack. The pair of spacer layers 306 a/b are formed from a material suchas silicon oxy-nitride, silicon nitride, silicon nitride doped withcarbon, or silicon carbide. Processes for forming sidewall spacersinclude deposition and etching process operations. In some embodiments,a plurality of spacer pairs may be used. For example, two pairs, threepairs, or four pairs of sidewall spacers may be formed on opposing sidesof the gate stack.

In some embodiments, depending on whether the transistor is to be ap-type or an n-type transistor, gate metal layer 307 may comprise atleast one P-type work-function metal or N-type work-function metal. Insome embodiments, gate metal layer 307 may comprise a stack of two ormore metal layers. In some embodiments, the two or more metal layers arework-function metal layers and at least one metal layer is a conductivefill layer. In some embodiments, for an n-type transistor, metals thatmay be used for the gate metal layer 307 include aluminum carbide,tantalum carbide, zirconium carbide, and/or hafnium carbide. In someembodiments, metal for gate metal layer 307 for n-type transistorinclude aluminum, hafnium, zirconium, titanium, tantalum, and theiralloys. An n-type metal layer may enable the formation of an n-type gatemetal layer 307 with a work function that is between about 3.9 eV andabout 4.2 eV. In some embodiments, metal of layer 307 includes one ofTiN, TiSiN, TaN, Cu, Al, Au, W, TiSiN, and/or Co. In some embodiments,metal of layer 307 includes one or more of Ti, N, Si, Ta, Cu, Al, Au, W,or Co. In some embodiments, for a p-type transistor, metals that areused for gate metal layer 307 include, but are not limited to,ruthenium, palladium, platinum, cobalt, nickel, and conductive metaloxides. An example of conductive oxide includes ruthenium oxide. Ap-type metal layer may enable the formation of a p-type gate metal layer307 with a work function that is between about 4.9 eV and about 5.2 eV.

In some embodiments, drain contact 308 b is coupled to vias 309 a/b,which are coupled to metal layer 310. Metal layer 310 is the bit-line,which extends along the y-axis. In some embodiments, source contact 308a is coupled to via 309 b. Any suitable material can be used for sourceand drain contacts 308 a/b and vias 309 a/b. For example, one or more ofTi, N, Si, Ta, Cu, Al, Au, W, and/or Co can be used for source and draincontacts 308 a/b and vias 309 a/b. In some embodiments, via 309 b iscoupled to FE capacitor Cfe that comprises a number of layers stackedtogether to form a planar capacitor. These layers may be extending in anx-plane when the capacitor is a planar capacitor, in accordance withsome embodiments. In some embodiments, the stack of layers includesrefractive inter-metallic 311 a/b as a barrier material; conductiveoxides 312 a/b, and FE material 313. In some embodiments, refractiveinter-metallic 311 a/b are removed and vias 390 a/b are in directcontact with conductive oxides 312 a/b.

In some embodiments, refractive inter-metallic 311 a/b maintains the FEproperties of the FE capacitor Cfe. In the absence of refractiveinter-metallic 311 a/b, the ferroelectric material or the paraelectricmaterial 313 of the capacitor may lose its potency. In some embodiments,refractive inter-metallic 311 a/b comprises Ti and Al (e.g., TiAlcompound). In some embodiments, refractive inter-metallic 311 a/bcomprises one or more of Ta, W, and/or Co. For example, refractiveinter-metallic 311 a/b includes a lattice of Ta, W, and Co. In someembodiments, refractive inter-metallic 311 a/b includes one of: Ti—Alsuch as Ti3Al, TiAl, and/or TiAl3. In some embodiments, refractiveinter-metallic 311 a/b includes one of: Ni—Al such as Ni3Al, NiAl3,and/or NiAl. In some embodiments, refractive inter-metallic 311 a/bincludes Ni—Ti, Ni—Ga, and/or Ni2MnGa. In some embodiments, refractiveinter-metallic 311 a/b includes FeGa, and/or Fe3Ga. In some embodiments,refractive inter-metallic 311 a/b includes borides, carbides, ornitrides. In some embodiments, TiAl material comprisesTi-(45-48)Al-(1-10)M (at X trace amount %), with M being at least oneelement from V, Cr, Mn, Nb, Ta, W, and Mo, and with trace amounts of0.1-5% of Si, B, and/or Mg. In some embodiments, TiAl is a single-phasealloy γ(TiAl). In some embodiments, TiAl is a two-phase alloyγ(TiAl)+α2(Ti3Al). Single-phase γ alloys contain third alloying elementssuch as Nb or Ta that promote strengthening and additionally enhanceoxidation resistance. The role of the third alloying elements in thetwo-phase alloys is to raise ductility (V, Cr, Mn), oxidation resistance(Nb, Ta) or combined properties. Additions such as Si, B and Mg canmarkedly enhance other properties. In some embodiments, barrier layer311 a is coupled to plate-line or powerline (PL) 315. In someembodiments, sidewall barrier seal 321 a/b (insulating material) isplaced around layers 311 a, 312 a, 313, 312 b, and 311 b along thesides, while the top and bottom surfaces of 311 a and 311 b are exposedfor coupling to metal layers, vias, or a metallic pedestal.

In some embodiments, PL metal layer 315 extends along the y-directionand parallel to the BL metal layer 310. Having the BL and the PLparallel to one another further improves the density of the memorybecause the memory array footprint is reduced, allowing columnmultiplexing (muxing), and sharing of sense-amplifier, and PL driversize reduction, in comparison to having BL and PL orthogonal to eachother. In some embodiments, gate metal 307 is coupled to a gate contact316, which is coupled to WL metal layer 317. WL metal layer 317 is usedas the word-line (WL). In some embodiments, WL metal layer 317 extendsorthogonal to BL metal layer 310 and PL metal layer 315. In someembodiments, WL metal layer 317 is also parallel to BL 310 and PL metallayer 315. Any suitable metal can be used for BL metal layer 310, PLmetal layer 315, and/or WL metal layer 317. For example, Al, Cu, Co, Au,or Ag can be used for BL metal layer 310, PL metal layer 315, and WLmetal layer 317.

In various embodiments, FE material 313 can be any suitable low voltageFE material that allows the FE material to switch its state by a lowvoltage (e.g., 100 mV). FE material 313 is listed with reference to FIG.2A. While various embodiments here are described with reference toferroelectric material for storing the charge state, the embodiments arealso applicable for paraelectric material. For example, FE material 313of various embodiments can be formed using paraelectric material insteadof ferroelectric material. In some embodiments, paraelectric materialincludes one of: SrTiO3, Ba(x)Sr(y)TiO3 (where x is −0.5, and y is0.95); HfZrO2; Hf—Si—O; La-substituted PbTiO3; or PMN-PT based relaxorferroelectrics.

In some embodiments, thickness t₃₁₁ of refractive inter-metallic layer311 a/b is in a range of 1 nm to 20 nm. In some embodiments, thicknesst₃₁₂ of the conductive oxide layers 312 a/b is in a range of 1 nm to 20nm. In some embodiments, thickness t₃₁₃ of the FE material (e.g.,perovskite, hexagonal ferroelectric, or improper ferroelectric) 313 a/bis in a range of 1 nm to 20 nm. In some embodiments, the lateralthickness t₃₂₁ of the sidewall barrier seal 321 a/b (insulatingmaterial) is in a range of 0.1 nm to 40 nm. In some embodiments, thelateral thickness L_(Cfe) of the capacitive structure (without sidewallbarrier) is in a range of 5 nm to 200 nm. In some embodiments, theheight H_(Cfe) of the capacitive structure is in a range of 10 nm to 200nm. In some embodiments, the FE capacitive structure is withoutrefractive inter-metallic layers 311 a/b. In that case, conductiveoxides layers 312 a/b are in direct contact with the contacts, vias, ormetals (e.g., PL, source/drain region contact of transistor MN). In someembodiments, sidewall barrier seal 321 a/b is not present. In one suchembodiment, the sidewalls of the layers 311 a/b, 312 a/b, and 313 are indirect contact with ILD (interlayer dielectric) such as SiO2.

FIG. 3B illustrates a 3D view of a 1T1C FE bit-cell 320 with plate-lineparallel to the bit-line, where the transistor is a planar transistorand where the capacitor is a planar capacitor with partially wrappedencapsulation, in accordance with some embodiments. 1T1C FE bit-cell 320is like bit-cell 300 but with encapsulation portions 321 c and 321 dthat are partially adjacent to sidewall barrier seal 321 a and 321 b,and refractive inter-metallic layers 311 a. In various embodiments,encapsulation portions 321 c and 321 d terminate into via 309 a. Thematerial for encapsulation portions 321 c and 321 d is same as those forsidewall barrier seal 321 a and 321 b.

FIG. 3C illustrates a 3D view of a 1T1C FE bit-cell 330 with plate-lineparallel to the bit-line, where the transistor is a planar transistorand where the capacitor is a planar capacitor with wrappedencapsulation, in accordance with some embodiments. 1T1C FE bit-cell 330is like 1T1C FE bit-cell 320 but with encapsulation portions 321 e and321 f that are partially adjacent to sidewall barrier seal 321 a and 321b, and refractive inter-metallic layers 311 b. In various embodiments,encapsulation portions 321 e and 321 f terminate into via 309 b. Thematerial for encapsulation portions 321 e and 321 f is the same as thosefor sidewall barrier seal 321 a and 321 b.

FIG. 3D illustrates a 3D view of a 1T1C FE bit-cell 340 with theplate-line parallel to the bit-line, where the transistor is anon-planar transistor and where the capacitor is a planar capacitor, inaccordance with some embodiments. In this example, BL 310 is on a metallayer below the metal layer for PL metal layer 315. FinFET is an exampleof a non-planar transistor. FinFET comprises a fin that includes source342 and drain 343 regions. A channel resides between the source andregions 342 and 343, respectively. The transistor MN can have multiplefins parallel to one another that are coupled to the same gate stack.The fins pass through the gate stack forming source and drain regions342 and 343, respectively. Other examples of non-planar transistorsinclude nano-wire transistors or nano-sheet transistors.

FIG. 3E illustrates a 3D view of a 1T1C FE bit-cell 350 with theplate-line parallel to the bit-line, where the transistor is anon-planar transistor and where the capacitor is a planar capacitor withpartially wrapped encapsulation, in accordance with some embodiments.1T1C FE bit-cell 350 is like 1T1C FE bit-cell 340 but with encapsulationportions 321 c and 321 d that are partially adjacent to sidewall barrierseal 321 a and 321 b, and refractive inter-metallic layers 311 a. Asdiscussed with reference to various embodiments, refractiveinter-metallic layers 311 a/b can be removed. In that case,encapsulation portions 321 c and 321 d are partially adjacent tosidewall barrier seal 321 a and 321 b and conductive oxide layer 312 a.

FIG. 3F illustrates a 3D view of a 1T1C FE bit-cell 360 with theplate-line parallel to the bit-line, where the transistor is anon-planar transistor and where the capacitor is a planar capacitor withwrapped encapsulation, in accordance with some embodiments. 1T1C FEbit-cell 360 is like 1T1C FE bit-cell 350, but with encapsulationportions 321 e and 321 f that are partially adjacent to sidewall barrierseal 321 a and 321 b, and refractive inter-metallic layers 311 b. Asdiscussed with reference to various embodiments, refractiveinter-metallic layers 311 a/b can be removed. In that case,encapsulation portions 321 c and 321 d are partially adjacent tosidewall barrier seal 321 a and 321 b and conductive oxide layers 312 aand 312 b.

In some embodiments, the memory bit-cells are laid out such that theyshare diffusion regions. In some embodiments, sharing the diffusionregion may not be necessary. However, for denser and improvedperformance sharing diffusion may be preferred. In some embodiments,bit-cells along a given row or column receive their respective shared PLalong the row or column, where the row or column-based sharing isdependent on PL being parallel to WL or PL being parallel to BL.

In some embodiments, when PL is parallel to WL, bit-cells having 1T1Cconfiguration that share the same WL also share the same PL connection.In some embodiments, in the case where PL is parallel to WL, bit-cellsthat share the same WL connection, also share the same PL connections.Here, pitch refers to the x and y dimensions of the bit-cell. Because ofthe small pitch, many bit cells can be packed in an array fashionleading to a high-density memory array. While the capacitive structureof various embodiments is shown as a rectangular structure, it can haveother shapes too. For example, the capacitive structure of variousembodiments can have a cylindrical shape with dimensions like the onedescribed with reference to the rectangular capacitive structure. Insome embodiments, the capacitive structure is a planar capacitor. Insome embodiments, the capacitive structure is a non-planar structure.

FIG. 4A illustrates pillar FE capacitor 400 including cross-sectionalviews and a 3D view, in accordance with some embodiments. In variousembodiments, FE pillar capacitor 400 is cylindrical in shape. In someembodiments, FE pillar capacitor 400 is rectangular in shape. Taking thecylindrical shaped case for example, in some embodiments, the layers ofFE pillar capacitor 400 from the center going outwards include oxidescaffolding 402, bottom electrode 401 a, first conductive oxide 412 a,FE material 413, second conductive oxide 412 b, and top electrode 401 b.A cross-sectional view along the “ab” dashed line is illustrated in themiddle of FIG. 4A. In some embodiments, bottom electrode 401 a isconformally deposited over oxide scaffolding 402 (e.g., SiO2 or anyother suitable dielectric). In some embodiments, first conductive oxide412 a is conformally deposited over bottom electrode 401 a. In someembodiments, FE material 413 is conformally deposited over firstconductive oxide 412 a. In some embodiments, second conductive oxide 412b is conformally deposited over FE material 413. In some embodiments,top electrode 401 b is conformally deposited over second conductiveoxide 412 b. In some embodiments, the oxide scaffolding is etched, andmetal is deposited into it which becomes part of bottom electrode 401 a.In some embodiments, a top section of FE pillar capacitor 400 that formsan upside-down ‘U’ shape is chopped off (e.g., by etching). This allowsbottom electrode 401 a to be accessible from the top and bottom of FEpillar capacitor 400, where bottom electrode 401 a is in the center,while top electrode 401 b is on an outer circumference of FE pillarcapacitor 400.

In some embodiments, wherein bottom electrode 401 a (herein first layer)has a first circumference, wherein first conductive oxide 412 a (hereinsecond layer) has a second circumference, wherein FE material 413(herein third layer) has a third circumference, wherein secondconductive oxide 412 b (herein fourth layer) has a fourth circumference,and wherein the top electrode 401 b (herein fifth layer) has a fifthcircumference. In some embodiments, the fourth circumference is largerthan the third circumference, wherein the third circumference is largerthan the second circumference, and wherein the second circumference islarger than the first circumference.

In various embodiments, the choice of materials for FE pillar capacitor400 are similar to the choice of material for the FE planar capacitor ofFIG. 3A. For example, the materials for FE pillar capacitor 400 can beselected from the same group of materials listed for the FE planarcapacitor FIG. 3A. For example, material for bottom electrode 401 acorresponds to a bottom electrode or via 309 b, material for conductiveoxide 312 b corresponds to first conductive oxide 412 a, FE material 413corresponds to FE material 313, material for second conductive oxide 312a corresponds to second conductive oxide 412 b, and material for a topelectrode or via 309 a corresponds to top electrode 401 b. In someembodiments, a first refractive inter-metallic layer (not shown) isformed between FE material 413 and first conductive oxide 412 a. In someembodiments, a second refractive inter-metallic layer (not shown) isformed between FE material 413 and second conductive oxide 412 b. Inthese cases, the first and second refractive inter-metallic layers aredirectly adjacent to their respective conductive oxide layers and to FEmaterial 413. Refractive inter-metallic maintains the FE properties ofthe FE material 413. In the absence of refractive inter-metallic,ferroelectric material 413 (or the paraelectric material) of pillarcapacitor 400 may lose its potency. In some embodiments, refractiveinter-metallic comprises Ti and Al (e.g., TiAl compound). In someembodiments, refractive inter-metallic comprises one or more of Ta, W,and/or Co. Material discussed with reference to layers 311 a and 311 bcan be used for the first and second refractive inter-metallic layers.The thicknesses of the layers of FE pillar capacitor 400 are of the samerange as similar layers discussed in FIG. 3A for a planar FE capacitor.FIGS. 4B-D illustrates various 3D view of memory bit-cells with planaror non-planar transistors, and with non-planar (or pillar) capacitor.Note, the various components, structures, or layers of this 1T1C FEbit-cell are described with reference to FIGS. 3A-G.

FIG. 4B illustrates a 3D view of a 1T1C FE bit-cell 420 with theplate-line parallel to the bit-line, where the transistor is a planartransistor MN and where the capacitor is a non-planar capacitor 400,where the bit-line is at a higher metal level than the plate-line, inaccordance with some embodiments.

FIG. 4C illustrates a 3D view of a 1T1C FE bit-cell 430 with theplate-line parallel to the bit-line, where the transistor is anon-planar transistor MN and where the capacitor is a non-planarcapacitor 400, where the bit-line is at a lower metal level than theplate-line, in accordance with some embodiments.

FIG. 4D illustrates a 3D view of a 1T1C FE bit-cell 440 with theplate-line parallel to the bit-line, where the transistor is anon-planar transistor and where the capacitor is a non-planar capacitor400, where the bit-line is at a higher metal level than the plate-line,in accordance with some embodiments.

FIG. 5A illustrates apparatus 500 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes two transistors and one capacitor(2T1C) with a plate-line parallel to a bit-line, in accordance with someembodiments. Apparatus 500 is like apparatus 200 of FIG. 2A but for adifferent kind of memory bit-cell. In some embodiments, each memorybit-cell in memory array 501 is organized in rows and columns like inapparatus 200. For example, memory bit-cells 501 _(0,0) through 501_(M,N) are organized in an array. In some embodiments, a memory bit-cell(e.g., 501 _(0,0)) comprises two transistors MN₁ and MN₂, and onecapacitor Cfe1 comprising non-linear polar material. Capacitor Cfe1 canbe a planar or non-planar capacitor as described with reference tovarious embodiments.

The gate terminals of n-type transistors MN₁ and MN₂ are controllable byWL (e.g., WL0). In some embodiments, BL (e.g., BL0) is coupled to asource or drain terminal of transistor MN₁. In some embodiments, PL(e.g., PL0) is coupled to the source or drain terminal of MN₂. While thevarious embodiments are illustrated with reference to n-typetransistors, the embodiments are also applicable to p-type transistorsor a combination of n-type or p-type transistors. A person skilled inthe art would appreciate that when transistors of different conductivitytype are used, than what is shown in FIG. 5A, then driving logic for BL,PL, and/or WL may also change for proper read and/or write operations.In various embodiments, PL is parallel to BL. In some embodiments,transistors MN₁ and MN₂ are fabricated in different layers of a die. Forexample, transistor MN₁ is fabricated on the frontend of the die whiletransistor MN₂ is fabricated in the backend of the die. On one suchembodiment, the capacitor Cfe is fabricated between the frontend and thebackend of the die. As such, a taller bit-cell is formed with the samex-y footprint as the footprint of a 1T1C memory bit-cell. In someembodiments, wear-leveling logic 206 provides one or more endurancemechanisms for the 2T1C memory bit-cells.

In some embodiments, in 2T1C bit-cell 501 _(0,0), there is a selecttransistor on either side of the storage element, which is capacitorCfe1. These two select transistors are MN₁ and MN₂ which arecontrollable by WL. To apply a signal for read or write operations alongany BL or PL of memory array 501, the select transistors for the desiredbit-cell is turned on. The select transistors see the applied field inproportion to the difference of voltage applied on BL, and PLs. Theunselected bit-cell may not see the disturb field due to transistor MN₂.Transistor MN₂ masks the signal visibility from BL, and also from thePL, in accordance with various embodiments. In some embodiments,transistor MN1 makes the visibility from the BL side for unselectedbit-cells. This helps mitigate the disturb effects seen otherwise withthe 1T1C configuration, where the PL voltage applied on an unselectedbit-line in conjunction with the parasitic capacitance at the storage orinternal node creates a disturb field effect. This disturb field effectstresses the long term retention characteristics of the programmedpolarized state of the FE capacitor Cfe1.

FIG. 5B illustrates apparatus 520 with FE memory with word-linerepeaters, wherein memory arrays of the FE memory have 2T1C bit-cellswith the plate-line parallel to the bit-line, in accordance with someembodiments. Apparatus 520 is like apparatus 240, but with memory arrays501-1 and 501-2. Timing diagrams for read and write operations for 2T1Cbit-cell is the same as timing diagrams for read and write operationsfor 1T1C bit-cell, respectively.

FIG. 6A illustrates apparatus 600 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes one transistor and multiplecapacitors (1TnC) with PLs parallel to a BL, where the correspondinglogic is to apply word-line boosting, in accordance with someembodiments. Apparatus 600 is like apparatus 200 of FIG. 2A but for adifferent kind of memory bit-cell. In some embodiments, each memorybit-cell in memory array 601 is organized in rows and columns like inapparatus 200. For example, memory bit-cells 601 _(0,0) through 601_(M,N) are organized in an array. In some embodiments, a memory bit-cell(e.g., 601 _(0,0)) comprises one select transistor MN₁ and a pluralityof capacitors Cfe1, Cfe2, through Cfen (where ‘n’ is a number greaterthan 1) comprising non-linear polar material (e.g., ferroelectric,paraelectric, or non-linear dielectric). The capacitors can be a planaror non-planar capacitor as described with reference to variousembodiments. In some embodiments, the plurality of capacitors Cfe1,Cfe2, through Cfen are stacked capacitors.

The gate terminal of transistors MN₁ is controllable by WL. In someembodiments, BL is coupled to a source or drain terminal of transistorMN₁. In some embodiments, an individual PL of a plurality of PLs iscoupled to an individual capacitor. For example, capacitor Cfe1 iscoupled to plate-line PL0_1, capacitor Cfe2 is coupled to plate_linePL0_2, and capacitor Cfen is coupled to plate_line PL0_n. In someembodiments, the plurality of capacitors is coupled to storage node sn1,which is coupled to a drain or source terminal of transistor MN₁. Forexample, a first terminal of capacitor Cfe1 is coupled to PL0_1 and asecond terminal of capacitor Cfe1 is coupled to storage node sn1.Apparatus 200 illustrates one PL per column. Apparatus 800 will haven-number of PLs (e.g., PL0_1 through PL0_n) per column which areparallel to a BL for that column, in accordance with some embodiments.

While the various embodiments are illustrated with reference to ann-type transistor, the embodiments are also applicable to a p-typetransistor or a combination of n-type or p-type transistors. A personskilled in the art would appreciate that when a transistor of adifferent conductivity type is used, than what is shown in FIG. 6A, thendriving logic for BL, PLs, and/or WL may also change for proper readand/or write operations. In various embodiments, PLs are parallel to BL.For example, PL0_1, PL0_2, PL0_n are parallel to BL. In someembodiments, transistor MN₁ is fabricated on the frontend of the die andcapacitors are stacked over the transistor. For example, the capacitorsare stacked along the z-direction. The capacitors can be planar ornon-planar capacitors. As such, a taller bit-cell is formed with thesame x-y footprint as the footprint of a 1T1C memory bit-cell. In someembodiments, the x-y footprint is determined by the size of transistorMN₁ and its connections to BL, WL, and storage node sn1.

In some embodiments, PL (e.g., PL0_1, PL0_2, . . . PL0_n) controls whichcapacitor of the bit-cell is programmed, and the value of programming Insome embodiments, BL acts as a sense-line. The voltage on BL (e.g.,sense voltage) can create disturbance on other bit-lines during readoperation. To mitigate such disturbances, in some embodiments, the 1TnCbit-cell is periodically refreshed (e.g., every 1 second). In someembodiments, periodic refresh is minimized by refreshing in active modeof operation. In standby mode (e.g., low power mode), the 1TnC bit-cellis not refreshed as there is no disturb mechanism during standby. Insome embodiments, wear-leveling logic 206 provides one or more endurancemechanisms for the 1TnC memory bit-cells. One of the endurancemechanisms involves refreshing of the data content in the capacitor(s).

In the 1TnC bit-cell case (e.g., bit-cell 601 _(0,0)) with PL parallelto BL, the activities seen on an unselected or un-intended bit-cellwhile performing read/write operations on the same column as that of theselected bit-cell can have large disturb effects on the unselected orunintended bit-cells. This may be true if the PL within the same columntoggles (during read or write) a particular value to the desiredbit-cell. This signal on the PL of that column, which is shared withother unselected cells, can create a field across the non-linear polarmaterial based capacitors or devices of the unselected cells. The fieldacross the unselected non-linear polar material based capacitors ordevices is a function of the dielectric component of individualnon-linear polar material based capacitors or devices and the totalcapacitance on the storage node sn1 of those bit-cells. Since in the1TnC bit-cells the storage capacitor have much larger capacitance load,the activity seen on the unselected bit-line can result into almost allvoltage getting dropped across the ferroelectric capacitors (e.g.,Vfe=Vpl*(Cp/(Cfed+Cp), which creates a disturb effect, which in turncauses unintentional modification of the polarization stage of theferroelectric capacitor.

FIG. 6B illustrates apparatus 620 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory have 1TnC bit-cellswith the PL parallel to the BL, in accordance with some embodiments.Apparatus 620 is like apparatus 240, but with memory arrays 601-1 and601-2. Each memory array includes the memory bit-cells of FIG. 6A.

FIG. 6C illustrates timing diagram 630 for write operation for 1TnC FEmemory bit-cells with plate-lines parallel to the bit-line, where thewrite operation involves word-line boosting, in accordance with someembodiments. In this case, PLs are parallel to the BL. Depending onwhether logic 1 (Write 1) or logic 0 (Write 0) is being written to theselected capacitor with non-linear polar material, BL or PL associatedwith that capacitor of the bit-cell is asserted from 0V to Vdd (powersupply level). Other column multiplexed BLs (e.g., BLy) and PLs (e.g.,PLy) that are inactive are forced to 0V, in accordance with someembodiments.

In various embodiments, write operation begins when WL is asserted andboosted above Vdd. The boost level is Vboost which may be 10-50% of Vdd.In one example, Vboost is about equal to a threshold voltage oftransistor MN₁ of the 1TnC bit-cell. WL boosting ensures that the fullvoltage swing is seen by the ferroelectric capacitors of the 1TnCbit-cell, negating the threshold (Vth) drop on the n-type transistorMN₁. WL boosting enables an overall lower voltage operation on the BLand PL drivers. This may use higher signal conditioning on the WL.

Since the select transistor MN₁ in these configurations is an n-channeldevice, it is good at passing the 0V and signals closer to 0V. Thesignal applied through the BL however, when it is at Vdd, may not passthrough the transistor MN₁ in full. As such, there is a Vt drop acrossthe transistor MN₁ if the WL is driven to Vdd. To help get the fullrange of signaling (e.g., 0 to Vdd) across the FE capacitor Cfe1,WL-boosting helps negate the Vt drop across the transistor such that BLwhen driven to Vdd, internal node will also see Vdd, as opposed toVdd−Vt.

In this example, the asserted WL0 is boosted for write operation (e.g.,to Vdd+Vboost), and then the selected BLx (e.g., BL0) and the selectedPL (e.g., PL0_1) are toggled to write a logic 1 or logic 0 to thecapacitor of interest. In this example, BLx and PL0_1 are toggled. Insome embodiments, to write a logic 1, BLx is toggled to Vdd when WL isboosted. In one such embodiment, PL1_0 is set to logic 0 to allowstorage of logic 1 value in capacitor Cfe1. In some embodiments, towrite a logic 0, BLx is kept at 0V when WL0 is boosted. In one suchembodiment, PL0_1 is set to logic 1 to allow storage of logic 1 value incapacitor Cfe1. The duration of pulse widths of BLx and PL0_1 issufficient to change the polarization state of the selected capacitorCfe1.

Other PLs (e.g., PL0_2 through n) within the same selected bit-cell(e.g., 601 _(0,0)) which are not programming their respective capacitorsare charged to Vdd/2. Like BLy, PL (e.g., PLy) for column multiplexedbit-cells remains at 0V while PL0_1 is being used to program Cfe1.Word-lines of unselected bit-cells is set to 0V (e.g., WL1, 2, through mare set to 0V when WL0 is selected).

When a particular bit-cell 601 _(0,0) is being written to, the WL forunselected bit-cells (e.g., WL1 through WLm) remains at 0. Same is donefor unselected BLs and PLs (e.g., BLy and PLy) by column multiplexers.In various embodiments, the BL or PLs are asserted and de-assertedwithin a pulse width of the boosted WL. In some embodiments, the voltageswing for the selected BL and PLs is 0 to Vdd. In some embodiments, theBL or PL pulse is generated after a predetermined or programmable timefrom when WL boost starts, and the BL or PL pulse ends within the WLpulse.

FIG. 6D illustrates timing diagram 640 for read operation for 1TnC FEmemory bit-cells with plate-lines parallel to the bit-line, where theread operation involves word-line boosting, in accordance with someembodiments. In some embodiments, read operation begins by asserting theselected WL (e.g., WL0). In some embodiments, the selected WL is boostedfor read operation. WL is boosted above Vdd to Vdd+Vboost level. In someembodiments, a writeback scheme is implemented after the read operationto restore the data value stored in the selected bit-cell due to thedestructive nature of the read operation. In one such embodiment, thedata which is read is also written back in the writeback time windowafter the read time window.

In some embodiments, BLx is set to 0V, and depending on whether a logic1 or a logic 0 is written during writeback to the selected capacitorCfe1 (via PL0_1), the selected bit-line is toggled. In this example,during writeback and during the pulse width of the boosted WL0, PL0_1and BLx is set to Vdd to write a 0 to the capacitor Cfe1. The writebackscheme here is the same as the writeback scheme of FIG. 6C. In thisscheme, the voltage swing on the selected capacitor is +/−Vdd.

In some embodiments, a selected PL (e.g., PL0_1) is asserted for thecapacitor of the bit-cell which is being read (e.g., capacitor Cfe1). Inthis example, PL0_1 is asserted for a time period long enough for thesense amplifier to sense the value stored on the storage node coupled tothe capacitor. In various embodiments, sense amplifier enable signal(SAE) is asserted within the pulse width of the selected PL (e.g.,PL0_1). In some embodiments, to read data from the storage node, BL isfirst set or forced to zero volts and then allowed to float (e.g., BLxdriver goes into high impedance state Z (HiZ)). In some embodiments, BLis precharged to a certain voltage or a programmable voltage. So, whenthe WL0 is selected, in conjunction with the PL voltage, a field iscreated across the FE capacitor.

Thereafter, the BL driver is configured in a high impedance stage, theselected BL is floated, which allows the sense amplifier to sense thevoltage on the storage node via the BL. In some embodiments, the senseamplifier is configured to sense the voltage on the BL by comparing itto one or more thresholds. In some embodiments, when BLx charges to afirst voltage level, a logic 0 is read (Read0). In some embodiments,when BLx charges to a second voltage level (higher than the firstvoltage level), a logic 1 is read (Read1). In some embodiments, afterthe sense amplifier is disabled (SAE is set to 0), the voltage on theselected BL is forced to zero volts. In some embodiments, after theselected BL is forced to 0V, the write back process begins. In someembodiments, the writeback process may not be needed if the readoperation is not a destructive read.

In some embodiments, in the write back process, BL is charged to Vdd orset to 0V depending upon whether a logic 1 or a logic 0 is written backto the selected bit-cell. In some embodiments, the value written back tothe bit-cell is the same value that the sense amplifier detects whenreading the voltage on the BL. In some embodiments, the write backmechanism is like the write operation described with reference to FIG.6C. In various embodiments, the WL for the unselected bit-cells is setto 0V (e.g., WL0, . . . WLm is set to 0 when WL1 is selected). Invarious embodiments, the BL and the PLs (e.g., PL0_2 through PL0_n) forthe unselected bit-cells is also set to 0V. In some embodiments,wear-leveling logic 206 is used for memory endurance of memory array1001.

FIG. 7A illustrates apparatus 700 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell is multi-element FE gain bit-cell with PLsparallel to a BL, where the corresponding logic is to apply word-lineboosting, in accordance with some embodiments. Apparatus 700 is likeapparatus 200 of FIG. 2A but for a different kind of memory bit-cell. Insome embodiments, each memory bit-cell (e.g., 701 _(0,0)) in memoryarray 701 is organized in rows and columns like in apparatus 700. Forexample, memory bit-cells 701 _(0,0) through 701 _(M,N) are organized inan array.

In some embodiments, a bit-cell (e.g., 701 _(0,0)) comprises n-typeselect transistor MN₁, n-type transistor MTR₁, bit-line (BL), word-line(WL), sense-line (SL), and ‘n’ number of ferroelectric (or paraelectric)capacitors Cfe1 through Cfen. In various embodiments, the gate terminalof the n-type transistor MN₁ is coupled to WL (e.g., WL1). In someembodiments, the drain or source terminal of the n-type transistor MN₁is coupled to BL. In various embodiments, first terminals of each of thecapacitors Cfe1 through Cfen is coupled to a storage node sn1. Thestorage node sn1 is coupled to a source or drain terminal of n-typetransistor MN₁ and to a gate of transistor MTR₁. In various embodiments,drain or source terminal of MTR₁ is coupled to a bias voltage Vs. Insome embodiments, Vs is a programmable voltage that can be generated byany suitable source. Vs voltage helps in biasing the gain transistor inconjunction with the sense-voltage that builds at sn1 node. In someembodiments, the source or drain terminal of transistor MTR₁ is coupledto SL (e.g., SL1). In some embodiments, a p-type transistor can be usedas well for gain.

In some embodiments, second terminals of each of the capacitors Cfe1through Cfen is coupled to a corresponding plate-line (PL). For example,the second terminal of Cfe1 is coupled to PL0_1, the second terminal ofCfe2 is coupled to PL0_2, and so on. Apparatus 700 has n-number of PLs(e.g., PL0_1 through PL0_n) per column which are parallel to a BL forthat column, in accordance with some embodiments. In some embodiments,the SL is parallel to the PL. In some embodiments, the SL is parallel tothe WL.

In some embodiments, ferroelectric (or paraelectric) capacitors Cfe1through Cfen are planar capacitors such as those discussed withreference to various embodiments herein. In some embodiments,ferroelectric (or paraelectric) capacitors Cfe1 through Cfen are pillarcapacitors such as those discussed with reference to various embodimentsherein. In some embodiments, the ferroelectric (or paraelectric)capacitors Cfe1 through Cfen are vertically stacked allowing for tallbit-cells (e.g., higher in the z-direction) but with x-y footprint twotransistors. By folding the capacitors, the diffusion capacitance on theBL reduces for a given array size, which improves reading speed.Further, folding the capacitors lowers the effective routing capacitanceon the BL. The larger footprint in the x-y direction of multi-element FEgain bit-cell compared to the footprint in the x-y direction of 1TnCbit-cell, vertical height of the capacitor can be reduced as thecapacitors can expand in the x-y direction more than before for a givenheight. As such, capacitors are folded more effectively. For example,n/2 capacitors per metal or via layer can be packed. In variousembodiments, more capacitors can be stacked in multi-element FE gainbit-cell because storage node sn1 is decoupled from the BL. Themulti-element FE gain bit-cell reduces the thickness scaling requirementfor the pillar capacitor. The polarization density requirements arereduced for multi-element FE gain bit-cell compared to 1TnC bit-cell.

In this example, the x-y footprint is determined by the size oftransistor MN₁ and its connections to BL, WL, and storage node sn1. Insome embodiments, the footprint can still be decided by other factorssuch as: a number of capacitors that connect to the node; how thecapacitors are arranged, e.g., more folding on the same node versusstacking; effective size constraints on those capacitors; and number ofcapacitors that share the same bit-cell. In some embodiments, PL (e.g.,PL0_1, PL0_2, . . . PL_n) controls which cell within the same accesstransistor gets programmed, and the value of programming In someembodiments, BL acts as a sense-line. The voltage on BL (e.g., sensevoltage) can create disturbance on other bit-lines during readoperation. To mitigate such disturbances, in some embodiments,multi-element FE gain bit-cell (e.g., 701 _(0,0)) is periodicallyrefreshed (e.g., every 1 second). In some embodiments, periodic refreshis minimized by refreshing in active mode of operation that can becoupled with advance schemes for wear leveling. In standby mode (e.g.,low power mode), multi-element FE gain bit-cell (e.g., 701 _(0,0)) isnot refreshed as there is no disturb mechanism during standby. In someembodiments, multi-element FE gain bit-cell (e.g., 701 _(0,0)) relies onisolating the read mode from BL or SL capacitance by isolating throughaccess transistor MN₁, where MN₁ transistor facilitates pre-charging thesn1 node, prior to read operation.

In some embodiments, there is a possibility of disturbance at thestorage node sn1 during read operation. In some embodiments, PL istoggled for other capacitors to the average value of the disturbancethat will be seen on the sn1 node. i.e., when a read pulse of somepolarity is applied at PL of the capacitor to be read, a non-zerovoltage is applied on other PLs of multi-element FE gain bit-cell (e.g.,701 _(0,0)), that matches the expected disturbance seen on the sharednode. In one such example, the PL driver is configured to supportdriving different voltage levels on different PLs. In some embodiments,wear-leveling logic 206 provides one or more endurance mechanisms forthe multi-element FE gain bit-cells. One of the endurance mechanismsinvolves refreshing of the data content in the capacitor(s).

FIG. 7B illustrates apparatus 720 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory have multi-element FEgain bit-cells with the PL parallel to the BL, in accordance with someembodiments. Apparatus 720 is like apparatus 240, but with memory arrays701-1 and 701-2. Each memory array includes the memory bit-cells of FIG.7A.

FIG. 7C illustrates timing diagram 730 for a first scheme for writeoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments. In some embodiments, thevoltage swing across the selected ferroelectric capacitor is Vdd duringwrite operation (e.g., the swing is ½ Vdd to −½ Vdd). To write to acapacitor of a multi-element FE gain bit-cell (e.g., 701 _(0,0)), WL tothat bit-cell is boosted. For example, WL0 is boosted to Vdd+Vboost. Insome embodiments, the BL (e.g., BLx) for multi-element FE gain bit-cellis set to ½ Vdd during the time the WL (e.g., WL0) is boosted. In someembodiments, the BLx is set to ½ Vdd prior to the WL boosting. In someembodiments, BLx remains charged to ½ Vdd even after WL0 boosting ends(e.g., for one or more cycles). To program a particular capacitor of themulti-element FE gain bit-cell, the plate-line for that capacitor isfirst set to ½ Vdd and then set to Vdd or ground during the pulse widthof the boosted WL0 to store a 0 or a 1 to that capacitor. In thisexample, PL0_1 is charged from 0V to Vdd/2 when BL is charged to Vdd/2.Then during the pulse width of the boosted WL0, PL0_1 is set to Vdd towrite a 0 to capacitor Cfe1. In some embodiments, during the pulse widthof the boosted WL0, PL0_1 is set to 0V to write a logic 1 to thecapacitor Cfe1. Other PLs (e.g., PL0_2 through n) within the sameselected bit-cell (e.g., 701 _(0,0)) are charged to Vdd/2 like Blx. PL(e.g., PLy) for column multiplexed bit-cells remains at 0V while PL0_1is being used to program Cfe1. Word-lines of unselected bit-cells is setto 0V (e.g., WL1, 2, through m are set to 0V when WL0 is selected). Invarious embodiments, sense-lines (SL) for all bit-cells are set to 0V,high-impedance, or Vs during the write operation. In variousembodiments, Vs for all bit-cells is set to 0V, high-impedance, or abias voltage (Vbias) during the write operation.

FIG. 7D illustrates timing diagram 740 for a second scheme for writeoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments. Compared to scheme 1described with reference to FIG. 7C, here instead of setting theselected BL (e.g., BLx) and the selected PL (e.g., PL0_1) to ½ Vdd, theyare set to 0V. WL is boosted for write operation (e.g., to Vdd+Vboost),and then the selected BL and the selected PL are toggled to write alogic 1 or logic 0 to the capacitor of interest. In this example, BLxand PL0_1 are toggled. In some embodiments, to write a logic 1, BLx istoggled to Vdd when WL is boosted. In one such embodiments, PL1_0 is setto logic 0 to allow storage of logic 1 value in capacitor Cfe1. In someembodiments, to write a logic 0, BLx is kept at 0V when WL0 is boosted.In one such embodiments, PL0_1 is set to logic 1 to allow storage oflogic 1 value in capacitor Cfe1. The duration of pulse widths of BLx andPL0_1 is sufficient to change the polarization state of the selectedcapacitor Cfe1.

Other PLs (e.g., PL0_2 through n) within the same selected bit-cell(e.g., 701 _(0,0)) are charged to Vdd/2 like Blx. PL (e.g., PLy) forcolumn multiplexed bit-cells remains at 0V while PL0_1 is being used toprogram Cfe1. By charging the PLy 0 ½Vdd reduces the disturb effect onthe unselected bit-cells. Word-lines of unselected bit-cells is set to0V (e.g., WL1, 2, through m are set to 0V when WL0 is selected). Invarious embodiments, sense-lines (SL) for all bit-cells are set to 0V,high-impedance, or Vs during the write operation. In variousembodiments, Vs for all bit-cells is set to 0V, high-impedance, or abias voltage (Vbias) during the write operation.

FIG. 7E illustrates timing diagram 750 for the first scheme readoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments. In some embodiments, readoperation begins by asserting the selected WL (e.g., WL0). In someembodiments, the selected WL is boosted for read operation. WL0 isboosted above Vdd to Vdd+Vboost level. In some embodiments, a writebackscheme is implemented after the read operation to ensure the readoperation does not corrupt the data value stored in the selectedbit-cell. In one such embodiment, the data which is read is also writtenback in the writeback time window after the read time window. In someembodiments, PL (e.g., PL0_1) is asserted for the bit-cell which isbeing read. Other unselected PLs (e.g., PL0_2, 3, through n) of thebit-cell (e.g., 701 _(0,0)) are kept at 0V during read operation, andthen to Vdd/2 during writeback if the first scheme is followed.

The PL (e.g., PL0_1) for the selected capacitor (e.g., Cfe1) of thebit-cell (e.g., 701 _(0,0)) is asserted for a time period long enoughfor the sense amplifier to sense the value stored on the storage nodecoupled to the capacitor. In various embodiments, sense amplifier enablesignal (SAE) is asserted within the pulse width of the PL. In someembodiments, to read data from the storage node sn1, BLx (e.g., BL0) isset or forced to zero volts during read operation, and then set to ½ Vddjust before WL0 is boosted for write back operation when the firstscheme is followed. Write back operation for the first scheme is likethe write operation discussed with reference to FIG. 7C. In someembodiments, the refresh mechanism is applied upon a read operation.This allows it to maintain the logic value in the bit-cell.

Referring to FIG. 7E, in some embodiments, storage node sn1 of theselected bit-cell SNx is precharged via BL and then floated. Here,“floating” means that there is no active driver for the node. In thiscase, the precharged voltage value acts as the initial bias voltage,which can then go down or up depending upon leakage characteristics atthat node, or due to ferroelectric capacitors on the SNx nodeinteracting with the read mechanism associated with PL pulsing. In someembodiments, SLx is precharged to a certain voltage or a programmablevoltage Vpch. SLx is then driven to a high impedance state Z.

At that point the PL (e.g., PL0_1) for the desired FE capacitor istoggled, which results into voltage buildup on the SNx node. The voltagebuild-up on the SNx node may be different voltage levels depending uponwhether the FE capacitor state was logic 0 or logic 1. Due to differentvoltage levels on the SNx node, the gain transistor MTR₁ may havedifferent conduction properties, which reduces the voltage levels on theSLx node (sense-line node) over time with different rates. For example,if SNx node voltage is corresponding to a logic 0 state, the conductanceof the gain transistor MTR₁ could be lower, and SLx voltage may decayslowly. For a logic 1 state, the conductance of the gain transistor MTR₁could be higher and may result into the SLx voltage going down faster.The time-sampling of this voltage relative to a reference expectedvalue, results in detection of the state in which the FE capacitor wasprogrammed After reading the value, a write-back operation can be doneto get the value restored to the FE capacitor, as reads are destructiveread in this configuration, in accordance with some embodiments.

In the write back process, the selected bit-cell BLx (e.g., BL0) ischarged to Vdd or set to 0V depending upon whether a logic 1 or a logic0 is written back to the selected bit-cell. The value written back tothe bit-cell is the same value that the sense amplifier detects whenreading the voltage on the BL. The write back mechanism is like thewrite operation described with reference to FIG. 7C. Here, here, ‘x’ inPLx_n indicates the same orientation as BL. For example, plate-linesPL0_1, PL0_2, and PL0_3 are parallel to BL0. Likewise, plate-linesPL1_1, PL1_2, and PL1_3 are parallel to BL1, and so on. In someembodiments, during the read operation, plate-lines that are not used toprogram a capacitor are set to 0. For example, PLy (e.g., PLy_1 throughn) are set to 0V while PL0_1 is being used to read from capacitor Cfe1.Here ‘y’ indicates all other PLs for unselected bit-cells.

FIG. 7F illustrates timing diagram 760 for the second scheme readoperation for multi-element FE gain bit-cells with the PL parallel tothe BL, in accordance with some embodiments. Compared to timing diagrams750, here the selected bit-line (BLx) is not set to ½ Vdd. In someembodiments, BLx is set to 0V, and depending on whether a logic 1 or alogic 0 is written during writeback to the selected capacitor Cfe1 (viaPL0_1), the selected bit-line is toggled. In this example, duringwriteback and during the pulse width of the boosted WL0, PL0_1 and BLxis set to Vdd to write a 0 to the capacitor Cfe1. The writeback schemehere is same as the writeback scheme of FIG. 7D. In this scheme (secondscheme), the voltage swing on the selected capacitor is +/−Vdd. In thescheme of FIG. 7E (first scheme), the voltage swing on the selectedcapacitor is +/−Vdd/2.

FIG. 8A illustrates apparatus 800 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes 1TnC bit-cells with PLs parallel toa BL, and with individual switches coupled to the capacitors on theplate-line side, where the corresponding logic is to apply word-lineboosting, in accordance with some embodiments. Apparatus 800 is likeapparatus 600, but with switches in the path of the plate-lines andhence a different kind of memory bit-cell. These switches are added toremove the charge disturb effect of unselected bit-cells when bit-linesare arranged parallel to the plate-lines. The charge disturb effect hereis on the stored state of the capacitors with non-linear polar material.By adding the switches, the plate-lines are no longer directly affectingthe charge disturb effect because of the corresponding WLs that controlthe switches.

In some embodiments, each memory bit-cell in memory array 801 isorganized in rows and columns like in apparatus 600, but with bit-linesrunning parallel to the plate-lines. For example, memory bit-cells 801_(0,0) through 801 _(M,N) are organized in an array. In someembodiments, n-type transistor MN_(PLO_1) is coupled to Cfe1 andplate-line PL0_1. In some embodiments, n-type transistor MN_(PLO_2) iscoupled to Cfe2 and plate-line PL0_2. Likewise, in some embodiments,n-type transistor MN_(PLO_n) is coupled to Cfen and plate-line PL0_n. Insome embodiments, n-type transistor MN_(PLB_x) is coupled tocompensation capacitor Cd and PLB_x. Each transistor (or switch) iscontrolled separately, in accordance with some embodiments. In someembodiments, transistor MN_(PLO_1) is controllable by WLP0_1, transistorMN_(PLO_2) is controllable by WLP0_2, and so on. Likewise, transistorMN_(PL0_n) is controllable by WLP0_n. Here, WLP0_1 . . . WLP0_n are theextensions of an address space. In this case, depending upon whichstorage element is being programmed or read, the corresponding WLP0_1 .. . WLP0_n are kept high (e.g., Vdd) whenever the plate-line voltage of0V or Vdd is applied, while the unselected storage element sees 0V.

While the various embodiments are illustrated with reference to n-typetransistors or switches, the embodiments are also applicable to a p-typetransistor or a combination of n-type or p-type transistors. A personskilled in the art would appreciate that when a transistor of adifferent conductivity type is used, than what is shown in FIG. 8A, thendriving logic for BL, PLs, WL, and/or WLPs may also change for properread and/or write operations.

In some embodiments, the switches added to the plate-lines arefabricated in different layers of a die. For example, transistor MN₁ isfabricated on the frontend of the die while transistors MN_(PLO_1),MN_(PLO_2), . . . and MN_(PLO_n), are fabricated in the backend of thedie. On one such embodiment, the capacitor Cfe is fabricated between thefrontend and the backend of the die. In one example, capacitors Cfe arevertically stacked capacitors. In some embodiments, each switch and itscorresponding coupled capacitor is formed in the backend of the die. Insome embodiments, each switch and its corresponding coupled capacitor isstacked vertically. For example, transistor MN_(PLO_1) and capacitorCfe1 are stacked vertically in a first vertical stack, and transistorMN_(PLO_2) and capacitor Cfe2 are stacked vertically in a secondvertical stack. These backed transistors or switches can be fabricatedusing any suitable technology such as IGZO (Indium gallium zinc oxide).

FIG. 8B illustrates apparatus 820 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory 1TnC bit-cells of FIG.8A, in accordance with some embodiments. Apparatus 820 is like apparatus240, but with memory arrays 801-1 and 801-2. Each memory array includesthe memory bit-cells of FIG. 8A.

FIG. 8C illustrates timing diagram 830 for write operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by a same signal, in accordance with some embodiments. In thisscheme (first scheme) all WLPs for switch transistors are driven by thesame signal per bit-cell, in accordance with some embodiments. Forexample, WLP0_1, WLP0_2, . . . WLP0_n for bit-cell 801 _(0,0) share thesame signal driver. In some embodiments, the signals on WLPs for switchtransistors for a bit-cell during the write operation are the same asthe WL0 signal for that bit-cell.

To write to a capacitor of a multi-element FE gain bit-cell (e.g., 801_(0,0)), WL to that bit-cell is boosted. For example, WL0 is boosted toVdd+Vboost. In some embodiments, the BL (e.g., BLx) for multi-element FEgain bit-cell is set to ½ Vdd during the time the WL (e.g., WL0) isboosted. In some embodiments, the BLx (e.g., BL0) is set to ½ Vdd priorto the WL boosting. In some embodiments, BLx remains charged to ½ Vddeven after WL0 boosting ends (e.g., for one or more cycles). To programa particular capacitor of the multi-element FE gain bit-cell, theplate-line for that capacitor is first set to ½ Vdd and then set to Vddor ground during the pulse width of the boosted WL to store a 0 or a 1to that capacitor. In this example, PL0_1 is charged from 0V to Vdd/2when BL0 is charged to Vdd/2. Then during the pulse width of the boostedWL, PL0_1 is set to Vdd to write a 0 to capacitor Cfe1. In someembodiments, during the pulse width of the boosted WL, PL0_1 is set to0V to write a 1 to the capacitor Cfe1.

Other PLs (e.g., PL0_2 through n) within the same selected bit-cell(e.g., 901 _(0,0)) are charged to Vdd/2 like Blx. PL (e.g., PLy) forcolumn multiplexed bit-cells remains at 0V while PL0_1 is being used toprogram Cfe1. Word-lines of unselected bit-cells are set to 0V (e.g.,WL1, 2, through M are set to 0V when WL0 is selected).

In some embodiments, the voltage swing across the selected ferroelectriccapacitor is Vdd during write operation (e.g., the swing is ½ Vdd to −½Vdd). For example, during write 0, BL0 is Vdd/2 and PL0_1 is Vdd, whichmakes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=−Vdd/2. Likewise, during write 1, BL0 is Vdd/2 and PL0_1 is 0,which makes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=Vdd/2.

As illustrated, in this scheme WLPs to the switches follow the samesignal as WL during the write operations, in accordance with someembodiments. For example, WPL0_1 associated with the capacitor Cfe1 tobe programmed and other WLPs (e.g., WLP0_2 through WLP0_n) are alsodriven to the same value as WLP0_1). In various embodiments, WLPs forinactive or unselected bit-cells are set to 0V just like WLs for theunselected bit-cells.

FIG. 8D illustrates timing diagram 840 for write operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by different signals, in accordance with some embodiments.Compared to scheme 1 described with reference to FIG. 8C, here theword-lines (WLPs) to the switches coupled to the plate-lines are drivenby different signals. Further, instead of toggling the selected BLx(e.g., BL0) and the selected PL (e.g., PL0_1) to ½ Vdd and thereaftertoggling the selected PL between 0V and Vdd for different write values,here both selected BL and selected PL are toggled between 0V and Vdddepending upon the write values.

In various embodiments, WL is boosted for write operation (e.g., WL0 isboosted to Vdd+Vboost), and then the selected BL and the selected PL aretoggled to write a logic 1 or logic 0 to the capacitor of interest. Inthis example, BLx and PL0_1 are toggled. In some embodiments, to write alogic 1, BLx is toggled to Vdd when WL is boosted. In one suchembodiment, PL0_1 is set to logic 0 to allow storage of logic 1 value incapacitor Cfe1. In some embodiments, to write a logic 0, BLx is kept at0V when WL is boosted. In one such embodiments, PL0_1 is set to logic 1to allow storage of logic 1 value in capacitor Cfe1. The duration ofpulse widths of BLx and PL0_1 is sufficient to change the polarizationstate of the selected capacitor Cfe1. All other plate-lines (e.g.,PL0_2, PL0_3, . . . PL0_n) remain at 0V when the selected PL (e.g.,PL0_1) is being used to program a capacitor in the bit-cell.

In various embodiments, for this scheme, the transistor coupled to thecapacitor being programmed is turned on during write operation, whileother switches for unselected capacitors remain off. For example, WLP0_1follows the same signal pattern as WL to turn on transistor MN_(PL0_1)to program capacitor Cfe1, while other WLPs (e.g., WLP0_2 throughWLP0_n) are set to 0V to keep the n-type switches off. In variousembodiments, other BLs which are unselected are set to 0V by a columnmultiplexer. In some embodiments, PLs of other unselected bit-cells andWLs of other unselected bit-cells are also kept at 0V to reduce anycross-noise.

Other PLs (e.g., PL0_2 through n) within the same selected bit-cell(e.g., 901 _(0,0)) are set to 0. PL (e.g., PLy) for column multiplexedbit-cells remains at 0V while PL0_1 is being used to program Cfe1.Word-lines of unselected bit-cells is set to 0V (e.g., WL1, 2, through Mare set to 0V when WL0 is selected).

In some embodiments, the voltage swing across the selected ferroelectriccapacitor is 2Vdd during write operation (e.g., the swing is Vdd to−Vdd). For example, during write 0, BL0 is 0 and PL0_1 is Vdd, whichmakes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=−Vdd. Likewise, during write 1, BL0 is Vdd and PL0_1 is 0,which makes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=Vdd.

As illustrated, in this scheme WLPs to the switches may not follow thesame signal as WL during the write operations, in accordance with someembodiments. For example, WPL0_1 associated with the capacitor Cfe1 tobe programmed and other WLPs (e.g., WLP0_2 through WLP0_n may not bedriven to the same value as WLP0_1. In various embodiments, WLPs forinactive or unselected bit-cells are set to 0V just like WLs for theunselected bit-cells. Scheme 2 simplifies signal generation compared toscheme 1 where tri-level signaling is used (e.g., scheme 1 usestri-level signaling in BL and PL). Here, 2-level signaling is used.Further, scheme 2 allows for a higher voltage swing on the ferroelectriccapacitor for a given supply, which effectively enables lower voltagesupply operation. While scheme 1 may share drivers for WLPs, here thedrivers for WLPs may be independent from one another.

FIG. 8E illustrates timing diagram 850 for read operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by a same signal, in accordance with some embodiments. In someembodiments, read operation begins by asserting the selected WL. In someembodiments, the selected WL is boosted for read operation. WL isboosted above Vdd to Vdd+Vboost level. In some embodiments, a writebackscheme is implemented after the read operation to restore the data valuestored in the selected bit-cell due to the destructive nature of theread operation. In one such embodiment, the data which is read is alsowritten back in the writeback time window after the read time window. Insome embodiments, PL (e.g., PL0_1) is asserted for the bit-cell which isbeing read. Other unselected PLs (e.g., PL0_2, PL_3, . . . PL0_n) of thebit-cell are kept at 0V during read operation, and then to Vdd/2 duringwriteback if the first scheme is followed. Here, here, ‘x’ in PLx_nindicates the same orientation as BL. For example, plate-lines PL0_1,PL0_2, and PL0_3 are parallel to BL0. Likewise, plate-lines PL1_1,PL1_2, and PL1_3 are parallel to BL1, and so on.

The PL for the selected capacitor of the bit-cell is asserted for a timeperiod long enough for the sense amplifier to sense the value stored onthe storage node coupled to the capacitor. In various embodiments, senseamplifier enable signal (SAE) is asserted within the pulse width of thePL. In some embodiments, to read data from the storage node, BLx (e.g.,BL0) is set or forced to zero volts during read operation, and then setto ½ Vdd just before WL is boosted for write back operation when thefirst scheme is followed. Writeback operation for the first scheme islike the write operation discussed with reference to FIG. 8C.

Referring to FIG. 8E, in some embodiments, storage node sn1 of theselected bit-cell SNx is precharged via BL and then floated. Here,“floating” means that there is no active driver for the node. In thiscase, the precharged voltage value acts as the initial bias voltage,which can then go down or up depending upon leakage characteristics atthat node, or due to ferroelectric capacitors on the SNx nodeinteracting with the read mechanism associated with PL pulsing. Invarious embodiments, selected BLx (e.g., BL0) follows similarcharacteristics as SNx during the read phase.

At that point the PL (e.g., PL0_1) for the desired FE capacitor istoggled, which results into voltage buildup on the SNx node. The voltagebuild-up on the SNx node may be different voltage levels depending uponwhether the FE capacitor state was logic 0 or logic 1. The time-samplingof this voltage relative to a reference expected value, results indetection of the state in which the FE capacitor was programmed Afterreading the value, a write-back operation can be done to get the valuerestored to the FE capacitor, as reads are destructive read in thisconfiguration, in accordance with some embodiments.

In various embodiments, the WLPs to the gates of the switches are drivenby a same signal. In some embodiments, during the read operation (whichincludes the writeback), WLPs are asserted to a boosted level (e.g.,Vdd+Vboost). In some embodiments, during the read operation, plate-linesthat are not used to program a capacitor are set to 0. For example,PL0_2 through n, PL1_0 through n are set to 0V while PL0_1 is being usedto read from capacitor Cfe1.

In some embodiments, WPL0_1 associated with the capacitor Cfe1 to beprogrammed and other WLPs (e.g., WLP0_2 through WLP0_n) are also drivento the same value as WLP0_1. In various embodiments, WLPs for inactiveor unselected bit-cells are set to 0V just like WLs for the unselectedbit-cells.

FIG. 8F illustrates timing diagram 860 for write operation for 1T1Cbit-cells with the PL parallel to the BL and where the word-lines (WLPs)for switch transistors for multiple plate-lines within a bit-cell aredriven by different signals, in accordance with some embodiments. Here,the writeback scheme is the same as that in FIG. 8D, in accordance withsome embodiments. In various embodiments, the read scheme in timingdiagram 860 is the same scheme as that of FIG. 8E, except for thesignals on other WLPs of the unselected capacitors of the same bit-cellare driven to 0V as opposed to the same value.

FIG. 9A illustrates apparatus 900 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes multi-element FE gain bit-cells withPLs parallel to a BL, and with individual switches coupled to thecapacitors on the plate-line side, where the corresponding logic is toapply word-line boosting, in accordance with some embodiments.

Apparatus 900 is like apparatus 700, but with switches in the path ofthe plate-lines and hence a different kind of memory bit-cell. Theseswitches are added to remove the charge disturb effect of unselectedbit-cells when bit-lines are arranged parallel to the plate-lines. Thecharge disturb effect here is on the stored state of the capacitors withnon-linear polar material. By adding the switches, the plate-lines areno longer directly affecting the charge disturb effect because of thecorresponding WLs that control the switches.

In some embodiments, each memory bit-cell in memory array 901 isorganized in rows and columns like in apparatus 700, but with bit-linesrunning parallel to the plate-lines. For example, memory bit-cells 901_(0,0) through 901 _(M,N) are organized in an array. In someembodiments, n-type transistor MN_(PLO_1) is coupled to Cfe1 andplate-line PL0_1. In some embodiments, n-type transistor MN_(PLO_2) iscoupled to Cfe2 and plate-line PL0_2. Likewise, in some embodiments,n-type transistor MN_(PLO_n) is coupled to Cfen and plate-line PL0_n.Each transistor (or switch) is controlled separately, in accordance withsome embodiments. In some embodiments, transistor MN_(PLO_1) iscontrollable by WLP0_1, transistor MN_(PLO_2) is controllable by WLP0_2,and so on. Likewise, transistor MN_(PL0_n) is controllable by WLP0_n.Here, WLP0_1 . . . WLP0_n are the extensions of an address space. Inthis case, depending upon which storage element is being programmed orread, the corresponding WLP0_1 . . . WLP0_n are kept high (e.g., Vdd)whenever the plate-line voltage of 0V or Vdd is applied, while theunselected storage element sees 0V.

While the various embodiments are illustrated with reference to ann-type transistors or switches, the embodiments are also applicable to ap-type transistor or a combination of n-type or p-type transistors. Aperson skilled in the art would appreciate that when a transistor of adifferent conductivity type is used, than what is shown in FIG. 9A, thendriving logic for BL, PLs, WL, and/or WLPs may also change for properread and/or write operations.

In some embodiments, the switches added to the plate-lines arefabricated in different layers of a die. For example, transistor MN₁ isfabricated on the frontend of the die while transistors MN_(PLO_1),MN_(PLO_2), and MN_(PLO_n), are fabricated in the backend of the die. Onone such embodiment, the capacitor Cfe is fabricated between thefrontend and the backend of the die. In one example, capacitors Cfe arevertically stacked capacitors. In some embodiments, each switch and itscorresponding coupled capacitor is formed in the backend of the die. Insome embodiments, each switch and its corresponding coupled capacitor isstacked vertically. For example, transistor MN_(PLO_1) and capacitorCfe1 are stacked vertically in a first vertical stack, and transistorMN_(PLO_2) and capacitor Cfe2 are stacked vertically in a secondvertical stack. These backed transistors or switches can be fabricatedusing any suitable technology such as IGZO (Indium gallium zinc oxide).

FIG. 9B illustrates apparatus 920 having FE memory with word-linerepeaters, wherein memory arrays of the multi-element FE gain bit-cellsof FIG. 9A, in accordance with some embodiments. Apparatus 920 is likeapparatus 240, but with memory arrays 901-1 and 901-2. Each memory arrayincludes memory bit-cells of FIG. 9A.

FIG. 9C illustrates timing diagram 930 for write operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by a same signal, in accordance with someembodiments. In this scheme (first scheme) all WLPs for switchtransistors are driven by a same signal per bit-cell, in accordance withsome embodiments. For example, WLP0_1, WLP0_2, . . . WLP0_n for bit-cell901 _(0,0) share a same signal driver. In some embodiments, the signalson WLPs for switch transistors for a bit-cell during the write operationare same as the WL0 signal for that bit-cell.

To write to a capacitor of a multi-element FE gain bit-cell (e.g., 901_(0,0)), WL to that bit-cell is boosted. For example, WL0 is boosted toVdd+Vboost. In some embodiments, the BL (e.g., BLx) for multi-element FEgain bit-cell is set to ½ Vdd during the time the WL (e.g., WL0) isboosted. In some embodiments, the BLx (e.g., BL0) is set to ½ Vdd priorto the WL boosting. In some embodiments, BLx remains charged to ½ Vddeven after WL0 boosting ends (e.g., for one or more cycles). To programa particular capacitor of the multi-element FE gain bit-cell, theplate-line for that capacitor is first set to ½ Vdd and then set to Vddor ground during the pulse width of the boosted WL to store a 0 or a 1to that capacitor. In this example, PL0_1 is charged from 0V to Vdd/2when BL0 is charged to Vdd/2. Then during the pulse width of the boostedWL, PL0_1 is set to Vdd to write a 0 to capacitor Cfe1. In someembodiments, during the pulse width of the boosted WL, PL0_1 is set to0V to write a 1 to the capacitor Cfe1.

Other PLs (e.g., PL0_2 through n) within the same selected bit-cell(e.g., 901 _(0,0)) are charged to Vdd/2 like Blx. PL (e.g., PLy) forcolumn multiplexed bit-cells remains at 0V while PL0_1 is being used toprogram Cfe1. Word-lines of unselected bit-cells is set to 0V (e.g.,WL1, 2, through M are set to 0V when WL0 is selected). In variousembodiments, sense-lines (SL) for all bit-cells are set to 0V,high-impedance, or Vs during the write operation. In variousembodiments, Vs for all bit-cells is set to 0V, high-impedance, or abias voltage (Vbias) during the write operation.

In some embodiments, the voltage swing across the selected ferroelectriccapacitor is Vdd during write operation (e.g., the swing is ½ Vdd to −½Vdd). For example, during write 0, BL0 is Vdd/2 and PL0_1 is Vdd, whichmakes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=−Vdd/2. Likewise, during write 1, BL0 is Vdd/2 and PL0_1 is 0,which makes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=Vdd/2.

As illustrated, in this scheme WLPs to the switches follow the samesignal as WL during the write operations, in accordance with someembodiments. For example, WPL0_1 associated with the capacitor Cfe1 tobe programmed and other WLPs (e.g., WLP0_2 through WLP0_n are alsodriven to the same value as WLP0_1). In various embodiments, WLPs forinactive or unselected bit-cells are set to 0V just like WLs for theunselected bit-cells.

FIG. 9D illustrates timing diagram 940 for write operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by different signals, in accordance withsome embodiments. Compared to scheme 1 described with reference to FIG.9C, here the word-lines (WLPs) to the switches coupled to theplate-lines are driven by different signals. Further, instead oftoggling the selected BLx (e.g., BL0) and the selected PL (e.g., PL0_1)to ½ Vdd and thereafter toggling the selected PL between 0V and Vdd fordifferent write values, here both selected BL and selected PL aretoggled between 0V and Vdd depending upon the write values.

In various embodiments, WL is boosted for write operation (e.g., WL0 isboosted to Vdd+Vboost), and then the selected BL and the selected PL aretoggled to write a logic 1 or logic 0 to the capacitor of interest. Inthis example, BLx and PL0_1 are toggled. In some embodiments, to write alogic 1, BLx is toggled to Vdd when WL is boosted. In one suchembodiment, PL0_1 is set to logic 0 to allow storage of logic 1 value incapacitor Cfe1. In some embodiments, to write a logic 0, BLx is kept at0V when WL is boosted. In one such embodiment, PL0_1 is set to logic 1to allow storage of logic 1 value in capacitor Cfe1. The duration ofpulse widths of BLx and PL0_1 is sufficient to change the polarizationstate of the selected capacitor Cfe1. All other plate-lines (e.g.,PL0_2, PL0_3, . . . PL0_n) remain at 0V when the selected PL (e.g.,PL0_1) is being used to program a capacitor in the bit-cell.

In various embodiments, for this scheme, the transistor coupled to thecapacitor being programmed is turned on during write operation, whileother switches for unselected capacitors remain off. For example, WLP0_1follows the same signal pattern as WL to turn on transistor MN_(PL0_1)to program capacitor Cfe1, while other WLPs (e.g., WLP0_2 throughWLP0_n) are set to 0V to keep the n-type switches off. In variousembodiments, other BLs which are unselected are set to 0V by a columnmultiplexer. In some embodiments, PLs of other unselected bit-cells andWLs of other unselected bit-cells are also kept at 0V to reduce anycross-noise.

Other PLs (e.g., PL0_2 through n) within the same selected bit-cell(e.g., 901 _(0,0)) are set to 0. PL (e.g., PLy) for column multiplexedbit-cells remains at 0V while PL0_1 is being used to program Cfe1.Word-lines of unselected bit-cells is set to 0V (e.g., WL1, 2, through Mare set to 0V when WL0 is selected). In various embodiments, sense-lines(SL) for all bit-cells are set to 0V, high-impedance, or Vs during thewrite operation. In various embodiments, Vs for all bit-cells is set to0V, high-impedance, or a bias voltage (Vbias) during the writeoperation.

In some embodiments, the voltage swing across the selected ferroelectriccapacitor is 2Vdd during write operation (e.g., the swing is Vdd to−Vdd). For example, during write 0, BL0 is 0 and PL0_1 is Vdd, whichmakes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=−Vdd. Likewise, during write 1, BL0 is Vdd and PL0_1 is 0,which makes the voltage across the selected ferroelectric capacitor Cfe1BL0−PL0_1=Vdd.

As illustrated, in this scheme WLPs to the switches may not follow thesame signal as WL during the write operations, in accordance with someembodiments. For example, WPL0_1 associated with the capacitor Cfe1 tobe programmed and other WLPs (e.g., WLP0_2 through WLP0_n) may not bedriven to the same value as WLP0_1. In various embodiments, WLPs forinactive or unselected bit-cells are set to 0V just like WLs for theunselected bit-cells. Scheme 2 simplifies signal generation compared toscheme 1 where tri-level signaling is used (e.g., scheme 1 usestri-level signaling in BL and PL). Here, 2-level signaling is used.Further, scheme 2 allows for a higher voltage swing on the ferroelectriccapacitor for a given supply, which effectively enables lower voltagesupply operation. While scheme 1 may share drivers for WLPs, here thedrivers for WLPs may be independent from one another.

FIG. 9E illustrates timing diagrams 950 for read operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by a same signal, in accordance with someembodiments. In some embodiments, read operation begins by asserting theselected WL. In some embodiments, the selected WL is boosted for readoperation. WL is boosted above Vdd to Vdd+Vboost level. In someembodiments, a writeback scheme is implemented after the read operationto restore the data value stored in the selected bit-cell due to thedestructive nature of the read operation. In one such embodiment, thedata which is read is also written back in the writeback time windowafter the read time window. In some embodiments, PL (e.g., PL0_1) isasserted for the bit-cell which is being read. Other unselected PLs(e.g., PL0_2, PL_3, . . . PL0_n) of the bit-cell are kept at 0V duringread operation, and then to Vdd/2 during writeback if the first schemeis followed. Here, here, ‘x’ in PLx_n indicates the same orientation asBL. For example, plate-lines PL0_1, PL0_2, and PL0_3 are parallel toBL0. Likewise, plate-lines PL1_1, PL1_2, and PL1_3 are parallel to BL1,and so on.

The PL for the selected capacitor of the bit-cell is asserted for a timeperiod long enough for the sense amplifier to sense the value stored onthe storage node coupled to the capacitor. In various embodiments, senseamplifier enable signal (SAE) is asserted within the pulse width of thePL. In some embodiments, to read data from the storage node, BL is setor forced to zero volts during read operation, and then set to ½ Vddjust before WL is boosted for write back operation when the first schemeis followed. Write back operation for the first scheme is like the writeoperation discussed with reference to FIG. 9C.

Referring to FIG. 9E, in some embodiments, storage node sn1 of theselected bit-cell SNx is precharged via BL and then floated. Here,“floating” means that there is no active driver for the node. In thiscase, the precharged voltage value acts as the initial bias voltage,which can then go down or up depending upon leakage characteristics atthat node, or due to ferroelectric capacitors on the SNx nodeinteracting with the read mechanism associated with PL pulsing. In someembodiments, SLx is precharged to a certain voltage or a programmablevoltage Vpch. SLx is then driven to a high impedance state Z.

At that point the PL (e.g., PL0_1) for the desired FE capacitor istoggled, which results into voltage buildup on the SNx node. The voltagebuild-up on the SNx node may be different voltage levels depending uponwhether the FE capacitor state was logic 0 or logic 1. Due to differentvoltage levels on the SNx node, the gain transistor MTR₁ may havedifferent conduction properties, which reduces the voltage levels on theSLx node over time with different rates. For example, if SNx nodevoltage is corresponding to a logic 0 state, the conductance of the gaintransistor MTR₁ could be lower, and SLx voltage may decay slowly. For alogic 1 state, the conductance of the gain transistor MTR₁ could behigher and may result into the SLx voltage going down faster. Thetime-sampling of this voltage relative to a reference expected value,results in detection of the state in which the FE capacitor wasprogrammed After reading the value, a write-back operation can be doneto get the value restored to the FE capacitor, as reads are destructiveread in this configuration, in accordance with some embodiments.

In various embodiments, the WLPs to the gates of the switches are drivenby the same signal. In some embodiments, during the read operation(which includes the writeback), WLPs are asserted to a boosted level(e.g., Vdd+Vboost). In some embodiments, during the read operation,plate-lines that are not used to program a capacitor are set to 0. Forexample, PL0_2 through n, PL1_0 through n are set to 0V while PL0_1 isbeing used to read from capacitor Cfe1.

In some embodiments, WPL0_1 associated with the capacitor Cfe1 to beprogrammed and other WLPs (e.g., WLP0_2 through WLP0_n are also drivento the same value as WLP0_1). In various embodiments, WLPs for inactiveor unselected bit-cells are set to 0V just like WLs for the unselectedbit-cells.

FIG. 9F illustrate timing diagram 960 for write operation formulti-element FE gain bit-cells with the PL parallel to the BL and wherethe word-lines (WLPs) for switch transistors for multiple plate-lineswithin a bit-cell are driven by different signals, in accordance withsome embodiments. Here, the writeback scheme is the same as that in FIG.9D, in accordance with some embodiments. In various embodiments, theread scheme in timing diagram 960 is the same scheme as that in FIG. 9E,except for the signals on other WLPs of the unselected capacitors of thesame bit-cell are driven to 0V as opposed to the same value.

FIG. 10A illustrates apparatus 1000 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell includes one transistor and an FE capacitorwith plate-line parallel to a word-line, where the corresponding logicis to apply word-line boosting, in accordance with some embodiments.

Apparatus 1000 comprises M×N memory array 1001 of bit-cells, logiccircuitry 202 for address decoding, and logic circuitry 1003 havingsense amplifier, write drivers, and plate-line (PL) driver. The PLs PL0,PL1, through PLm are parallel to respective WLs WL0, WL1, through WLm,while BLs BL0, BL1, through BLn are orthogonal to PLs and WLs. In someembodiments, bit-cell 1001 _(0,0) comprises a WL (e.g., WL0), a PL(PL0), and a BL (BL0). In some embodiments, bit-cell 1001 _(0,0)comprises an n-type transistor MN₁, and FE capacitive structure Cfe₁.The gates of transistor MN₁ are coupled to a common WL (e.g., WL0). Invarious embodiments, one terminal of the FE capacitive structure Cfe₁ iscoupled to a PL (e.g., PL0). The second terminal of the FE capacitivestructure is coupled to the source or drain terminal of the transistorMN₁. In various embodiments, BL (e.g., BL0) is coupled to the source ordrain terminal of first transistor MN₁. In some embodiments, a BLparasitic capacitor Cbl₁ is coupled to the source or drain terminal ofthe first transistor MN₁ and to a reference node (e.g., ground) suchthat the FE capacitor is not coupled to the same source or drainterminal. In some embodiments, the PL is parallel to the WL andorthogonal to the BL. In some embodiments, the FE capacitor is a planarcapacitor. In some embodiments, the FE capacitor is a pillar ornon-planar capacitor.

Logic circuitry 202 comprises address decoders for selecting a row ofbit-cells and/or a particular bit-cell from M×N memory array 1001, whereM and N are integers of same or different values. In some embodiments,logic circuitry 202 includes word-line drivers. In some embodiments,logic circuitry 203 comprises sense-amplifiers for reading the valuesfrom the selected bit-cell. Since the PL is parallel to the WL, in someembodiments, PL drivers and WL drivers are grouped together in logic1004. In various embodiments, write drivers are used to write aparticular value to a selected bit-cell. Here, a schematic of FEbit-cell 1001 _(0,0) is illustrated. The same embodiments apply to otherbit-cells of M×N array 1001.

In this example, a one-transistor one-capacitor (1T1C) bit cell isshown, but the embodiments are applicable to 1TnC bit-cell andmulti-element FE gain bit-cell as described herein. As the PL isparallel to the WL, the BL drivers can be placed orthogonal to theregion where the PL drivers and WL drivers are placed. In someembodiments, WL repeaters 205 are added to buffer the word-line signalsalong different memory arrays. In some embodiments, apparatus 1000comprises wear-leveling logic 206 (also referred to as refresh logic) torefresh the contents of the memory bit-cells periodically or on aneed-by-need basis.

In a PL parallel to WL topology, compared to the PL parallel to the BLtopology, the inherent issue with the signal toggle associated with anunselected bit-cell seeing signal activity on the PL may not happen.Thus, the PL parallel to WL topology is more immune to disturb effects,as inherently in a 1T1C configuration. In the PL parallel to the WL,merely the selected cells see the activities on the PL and the WL. Inthis case, the BL activities on the un-selected bit-cells are masked bythe transistors MN₁ of the un-selected bit-cells. In some embodiments,the PL parallel to WL topology helps enable longer retention, andpromises non-volatility without requiring additional transistors as inthe 2T1C bit-cell topology with PL parallel to the BL. In someembodiments, the PL parallel to WL topology also helps with amortizingthe cost of PL switching. As PL switching causes more bit-cells to beread, the parasitic capacitance from the PL switching gets amortizedacross multiple bit-cells, as opposed to the case when the PL isparallel to the BL. In the bit-cell topology with PL parallel to the BL,PL capacitance switching cost is on a per bit-cell basis. In someexamples, the bit-cell with PL parallel to WL topology comes with a costof lower speed and lower array efficiency due to difficulties inimplementing column-multiplexing technology. Thus, larger senseamplifier area may be used, which may adversely impact array efficiency.In some cases, the bit-cell with PL parallel to WL topology may uselarge PL drivers than for the case of bit-cells with PL parallel to theBL. In one such case, as every driver switches a greater number offerroelectric capacitors, there may be loss in array efficiency.

FIG. 10B illustrates apparatus 1020 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory have 1T1C bit-cellswith the plate-line parallel to the word-line, in accordance with someembodiments. Apparatus 1020 illustrates two instances of apparatus 1000.The two instances include first memory array 1001-1, logic circuitry202-1 having first address decoder and/or WL driver, logic circuitry1003-1 having first sense amplifier and BL driver, logic circuitry1004-1 having PL and WL repeaters; and second memory array 1001-2, logiccircuitry 202-2 having first address decoder and/or WL driver, logiccircuitry 1003-2 having first sense amplifier and BL driver, and logiccircuitry 1004-2 having PL and WL repeaters. In some embodiments, anindividual instance of apparatus 1000 includes a correspondingwear-leveling logic 206 (e.g., wear-leveling logic 206-1 andwear-leveling logic 206-2).

In some embodiments, when the pulsing scheme described herein iscombined with the refresh function by wear-leveling logic 206-1 andwear-leveling logic 206-2, disturb issues on unselected bit-cells aremitigated. While two memory arrays are shown (e.g., array 1001-1 and1001-2), any number of arrays may be part of apparatus 1020. With PLparallel to the WL and orthogonal to the BL, logic circuitries 1004-1and 1004-2 etc., having PL and WL repeaters are added to improve thedriving strength of the plate-line signals and the word-line signals. Insome embodiments, BL repeaters operate on Vdd supply while WL repeatersoperate on a higher power supply level (e.g., Vdd+Vboost) to implementWL boosting.

FIG. 10C illustrates timing diagram 1030 for write operation for 1T1C FEmemory bit-cells with plate-line parallel to the word-line, where thewrite operation involves word-line boosting, in accordance with someembodiments. In this case, PL is parallel to the WL. Depending onwhether logic 1 (Write 1) or logic 0 (Write 0) is being written to thecapacitor with non-linear polar material, BL or PL for that bit-cell isasserted from 0V to Vdd (power supply level). For example, BLx isinitially forced to zero volts, and then pulsed to Vdd to write a logic1, or continues to remain at 0V to write 0 to the bit-cell. In variousembodiments, when BLx is set to write a logic 1 or a logic 0, theselected PL (e.g., PL1) is pulsed within the duration when BLx is set towrite a logic 1 or a logic 0. For example, PL1 is pulsed within a pulsewidth of BLx during a logic write 1 operation.

In various embodiments, write operation begins when WL is asserted andboosted above Vdd. The boost level is Vboost which may be 10% to 50% ofVdd. In one example, Vboost is about 1× to 1.5× of a threshold voltage(Vt) of transistor MN of the 1T1C bit-cell.

Since, the select transistor in these configurations is an n-channeldevice, it is good at passing the 0V and signals closer to it. Thesignal applied through the BL however, when it is at Vdd, may not passthrough the transistor MN₁ in completeness. As such, there is a Vt dropacross the transistor MN₁ if the WL is driven to Vdd. To help get thefull range of signaling across the FE capacitor Cfe1, WL-boosting helpsnegate the Vt drop across the transistor such that BL when driven toVdd, internal node will also see Vdd, as opposed to Vdd−Vt.

For the bit-cell topology with PL parallel to the WL, the word-lineboosting is used as otherwise it can lead to a buildup of a voltagelevel of approximately 2× Vdd, when BL line is at Vdd, and PL voltagerises from 0V to Vdd. Since, with WL at Vdd, the transistor MN₁ can beoff with BL at Vdd, the storage node will sit at Vdd−Vt when PL is at0V. After that when PL goes from 0V to Vdd, the internal node can jumpto 2Vdd−Vt level. When WL is voltage boosted, and the PL voltage risesfrom 0V to Vdd, the storage node or internal node may not see thevoltage spike, as the transistor MN₁ may still be in the on condition.This helps with the reliability aspect of the transistor MN₁. Note, alarge voltage buildup on the storage node or internal node of thetransistor can cause lifetime degradation and thus yield issues.

When a particular bit-cell (e.g., 1001 _(0,0)) is being written to (herecell associated with WL1), the WLs for unselected bit-cells (e.g., WL0,WL1, through WLm) remains at 0V. Same is done for unselected PLy (e.g.,PL0, PL2, . . . PLm) by column multiplexers. Column multiplexing mayreduce an overhead of the peripheral circuitry (not shown). In someembodiments, column multiplexing may not be used to avoid any disturbeffect on unselected bit-cells. In some embodiments, the unselected BLs(e.g., BLy) are set to a voltage between 0V and Vdd (e.g., Vdd/2) bycolumn multiplexers. In some embodiments, the pulse width of theunselected BLs is substantially the same as the pulse width of theboosted WL (e.g., WL1).

In this example, the selected WL is WL0 and selected BL and PL are BLx(e.g., BL0) and PL0, respectively. In various embodiments, the BL and PLfor the selected bit-cell are asserted and de-asserted within a pulsewidth of the boosted WL (e.g., WL0). In some embodiments, the voltageswing for BL and PL is between 0 to Vdd. In some embodiments, BL or PLpulse is generated after a predetermined or programmable time from whenWL boost starts.

FIG. 10D illustrates timing diagram 1040 for read operation for 1T1C FEmemory bit-cells with the plate-line parallel to the word-line, wherethe read operation involves word-line boosting, in accordance with someembodiments. In some embodiments, read operation begins by asserting theselected WL. In some embodiments, the selected WL is boosted for readoperation. Selected WL (e.g., WL0) is boosted above Vdd to Vdd+Vboostlevel. In some embodiments, a writeback scheme is implemented after theread operation to restore the data value stored in the selected bit-celldue to the destructive nature of the read operation. In one suchembodiment, the data which is read is also written back in the writebacktime window after the read time window. In some embodiments, PL (e.g.,PL0) is asserted for the bit-cell which is being read. PL0 is assertedfor a time period long enough for the sense amplifier to sense the valuestored on the storage node coupled to the capacitor. In variousembodiments, sense amplifier enable signal (SAE) is asserted within thepulse width of the PL0. In some embodiments, to read data from thestorage node, BL is first set or forced to zero volts and then allowedto float (e.g., BL driver goes into high impedance state Z (HiZ)). Insome embodiments, BL0 is precharged to a certain voltage or aprogrammable voltage. So, when the WL is selected, in conjunction withthe PL voltage, a field is created across the FE capacitor.

Thereafter, the BL driver is configured in high impedance state, theselected BL0 is floated, which allows the sense amplifier to sense thevoltage on the storage node via the BL (e.g., BL0). In some embodiments,the sense amplifier is configured to sense the voltage on the BL bycomparing it to one or more thresholds. In some embodiments, when BL(e.g., BL0) charges to a first voltage level, a logic 0 is read (Read0).In some embodiments, when BL (e.g., BL0) charges to a second voltagelevel (higher than the first voltage level), a logic 1 is read (Read1).In some embodiments, after the sense amplifier is disabled (SAE is setto 0, in this example), the voltage on the selected BL is forced to zerovolts. In some embodiments, after the selected BL is forced to 0V, thewrite back process begins.

In the write back process, the selected bit-cell BL (e.g., BLx) ischarged to Vdd or set to 0V depending upon whether a logic 1 or a logic0 is written back to the selected bit-cell. The value written back tothe bit-cell is the same value that the sense amplifier detects whenreading the voltage on the BL. The write back mechanism is like thewrite operation described with reference to FIG. 10C. In variousembodiments, the WL for the unselected bit-cells is set to 0V (e.g.,WL1, WL2, . . . WLm is set to 0 when the selected WL0 is selected). Invarious embodiments, the BL for the unselected bit-cells (e.g., BLy) isset between 0 and Vdd (e.g., Vdd/2) by column multiplexing, for example,during the read and writeback operations.

One reason for setting BLy to Vdd/2 is to minimize the disturb effectson the column-multiplexed BLs, as for them the PL voltage still togglesbetween 0V to Vdd. If BLy is set to Vdd/2, then the disturb fields arelimited to +/−Vdd/2, in accordance with some embodiments. In someembodiments, to minimize the disturb effect it may not be desirable todo any column multiplexing itself, as it may mean loss of retentioncharacteristic over long time scale to other bit-cells that are notgetting programmed, as +/−Vdd/2 disturb may cause fast retention loss.

This is done to minimize the disturb effects on the column-muxed BLs, asfor them the PL voltage still toggles between 0 to 1. If BLy is set toVdd/2, then the disturb fields are limited to +/−Vdd/2. Note: in someembodiments, to minimize disturb affect one may not want to do anycolumn muxing itself, as it means loss of retention characteristic overlong time scale to other cells that are not getting programmed, as+/−Vdd/2 disturb may cause fast retention loss. In some embodiments, thePLs for the unselected bit-cell (e.g., PL1, PL2, . . . PLm) is set to 0Vduring read and writeback operations. In some embodiments, the WLs forthe unselected bit-cell (e.g., WL1, WL2, . . . WLm) is set to 0V duringread and writeback operations.

FIG. 11A illustrates apparatus 1100 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell is multi-element FE gain bit-cell withplate-lines parallel to a word-line, where the corresponding logic is toapply word-line boosting, in accordance with some embodiments. Apparatus1100 is like apparatus 820 of FIG. 8B but for WL parallel to PLs. Insome embodiments, each memory bit-cell in memory array 1101 is organizedin rows and columns like in apparatus 820. For example, memory bit-cells1101 _(0,0) through 1101 _(M,N) are organized in an array. Like in FIG.10A, where WL is parallel to PL, PL drivers and WL drivers are lumped inlogic 1004 orthogonal to BL drivers in logic circuitry 203, inaccordance with some embodiments.

FIG. 11B illustrates apparatus 1120 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory have 1TnC bit-cellswith the plate-lines parallel to the word-line, in accordance with someembodiments. Apparatus 1120 illustrates two instances of apparatus 1100.The two instances include first memory array 1101-1, logic circuitry202-1 having first address decoder and/or WL driver, logic circuitry1003-1 having first sense amplifier and BL driver, logic circuitry1104-1 having PL and WL repeaters; second memory array 1101-2, logiccircuitry 202-2 having first address decoder and/or WL driver, logiccircuitry 1003-2 having first sense amplifier and BL driver, and logiccircuitry 1104-2 having PL and WL repeaters. In some embodiments, anindividual instance of apparatus 1100 includes a correspondingwear-leveling logic 206 (e.g., wear-leveling logic 206-1 andwear-leveling logic 206-2). In some embodiments, when the pulsing schemedescribed herein is combined with the refresh function by wear-levelinglogic 206-1 and wear-leveling logic 206-2, disturbance issues onunselected bit-cells are mitigated. While two memory arrays are shown(e.g., memory arrays 1101-1 and 1101-2), any number of arrays may bepart of apparatus 1120. With PL parallel to the WL and orthogonal tologic circuitries 1104-1, 1104-2 etc. having BL, PL and WL repeaters areadded to improve the driving strength of the plate-line signals and theword-line signals. In some embodiments, BL repeaters operate on Vddsupply while WL repeaters operate on a higher power supply level (e.g.,Vdd+Vboost) to implement WL boosting.

FIG. 11C illustrates timing diagram 1130 for write operation formulti-element FE gain bit-cells with plate-line parallel to theword-line, where the write operation involves word-line boosting, inaccordance with some embodiments. In this case, PLs are parallel to theWL. Depending on whether logic 1 (Write 1) or logic 0 (Write 0) is beingwritten to the selected capacitor with non-linear polar material, BL, orPL (e.g., BLx and PL0_1) associated with that capacitor of the bit-cell(e.g., 1101 _(0,0)) is asserted from 0V to Vdd (power supply level).Other WLs or PLs not part of the bit-cell are forced to 0V. In someembodiments, other PLs (e.g., PL0_2, PL0_3, . . . PL0_n) of the selectedbit-cell (e.g., 1101 _(0,0)) are set between 0 and Vdd (e.g., Vdd/2). Insome embodiments, PL of the unselected bit-cells (e.g., PL1_0, . . .PL1_n to PLm_0, . . . PLm_n) are set to 0V. In some embodiments, the WLsfor the unselected bit-cells (e.g., WL1, WL2, . . . WLm) are set to 0V.

In various embodiments, write operation begins when WL is asserted andboosted above Vdd. The boost level is Vboost which may be 10-50% of Vdd.In one example, Vboost is about 1× to 1.5× of a threshold voltage (Vt)of transistor MN of the 1T1C bit-cell. Since, the select transistor inthese configurations is an n-channel device, it is good at passing the0V and signals closer to it. The signal applied through the BL however,when it is at Vdd, may not pass through the transistor MN₁ incompleteness. As such, there is a Vt drop across the n-type transistorMN₁ if the WL is driven to Vdd. To help get the full range of signalingacross the FE capacitor Cfe1, WL-boosting helps negate the Vt dropacross the transistor such that BL when driven to Vdd, internal nodewill also see Vdd, as opposed to Vdd−Vt.

For the bit-cell topology with PL parallel to the WL, the word-lineboosting is used as otherwise it can lead to a buildup of a voltagelevel of approximately 2× Vdd on the storage node sn1, when BL line isat Vdd, and PL goes from 0V to Vdd. Since, with WL at Vdd, thetransistor MN₁ can be off with BL at Vdd, the storage node sn1 will sitat Vdd−Vt when PL is at 0V. After that when PL goes from 0V to Vdd, theinternal node can jump to 2Vdd−Vt level. When WL is voltage boosted, andthe PL voltage rises from 0V to Vdd, the storage node or internal nodemay not see the voltage spike, as the transistor MN₁ may still be in theon condition. This helps with the reliability aspect of the transistorMN₁. Note, a large voltage buildup on the storage node or internal nodeof the transistor can cause lifetime degradation and correspondinglyyield issues.

When a particular bit-cell (e.g., 1101 _(0,0)) is being written to, theWL for unselected bit-cells (e.g., WL0 through WLm) remains at 0. Sameis done for unselected PLs as illustrated. Timing diagram 1130 is afirst order diagram without column multiplexing. A person skilled in theart would appreciate that column multiplexing is used for accessingmemory bit-cells in an array. Here. all BLs within an active array aretoggled according to what is being written. Since the BLs are orthogonalto the WL, and PL is being toggled, BLs are driven either 0 or 1,depending on what is being written. In some embodiments, when columnmultiplexing is implemented, the corresponding BL lines of inactivebit-cells are set to Vdd/2 to minimize the disturb effect on thosebit-cells. Column multiplexing may reduce an overhead of the peripheralcircuitry (not shown). In some embodiments, column multiplexing may notbe used to avoid any disturb effect on unselected bit-cells.

In various embodiments, the BL and PL for the selected bit-cellcapacitor are asserted and de-asserted within a pulse width of theboosted WL. In some embodiments, the voltage swing for BL and PL isbetween 0 to Vdd. In some embodiments, the selected PL (PL1_0) isasserted and de-asserted within the pulse width of BLx (e.g., BL0). Insome embodiments, unselected PLs of the selected bit-cells are parked ata lower voltage (e.g., Vdd/2) to limit the disturb effect on thosecapacitors due to voltage on the internal node sn1 being either Vdd or0. This limits the disturbance as seen by other ferroelectric capacitorsof the selected bit-cells. The pulse width of the unselected PLs (e.g.,PL0_2, PL0_3, . . . PL0_n), of the selected bit-cell is substantiallythe same as the pulse width of the boosted WL (e.g., WL0), in accordancewith some embodiments.

In some embodiments, the BL or PL pulse is generated after apredetermined or programmable time from when WL boost starts, and the BLor PL pulse ends within the WL pulse. In one example, to write a logic 1to all capacitors Cfe1 through Cfen, BL pulse is generated within thepulse width of the boosted WL. All other PLs for the unselected bit-cellare set to 0V (e.g., PL1_1, PL1_2, through PL1_n are forced to 0V, andlikewise PL2_1, PL2_2, through PL2_n are forced to 0V, and so on).

PLs (e.g., PL0_2 through n) within the same selected bit-cell (e.g.,1101 _(0,0)) are charged to Vdd/2, in accordance with variousembodiments. In some embodiments, PL for unselected bit-cells remains at0V while PL0_1 is being used to program capacitor Cfe1. Word-lines ofunselected bit-cells are set to 0V (e.g., WL1, 2, through M are set to0V when WL0 is selected). In various embodiments, sense-lines (SL) forall bit-cells are set to 0V, high-impedance, or Vs during the writeoperation. In various embodiments, Vs for all bit-cells is set to 0V,high-impedance, or a bias voltage (Vbias) during the write operation.

FIG. 11D illustrates timing diagram 1140 for read operation formulti-element FE gain bit-cells with plate-line parallel to theword-line, where the read operation involves word-line boosting, inaccordance with some embodiments. In some embodiments, read operationbegins by asserting the selected WL. In some embodiments, the selectedWL is boosted for read operation. WL is boosted above Vdd to Vdd+Vboostlevel. In some embodiments, a writeback scheme is implemented after theread operation to restore the data value stored in the selected bit-celldue to the destructive nature of the read operation. In one suchembodiment, the data which is read is also written back in the writebacktime window after the read time window. In some embodiments, PL isasserted for the bit-cell which is being read.

In some embodiments, PL for the selected capacitor of the bit-cell isasserted for a time period long enough for the sense amplifier to sensethe value stored on the storage node coupled to the capacitor. Invarious embodiments, sense amplifier enable signal (SAE) is assertedwithin the pulse width of the PL. In some embodiments, to read data fromthe storage node, BL is set or forced to zero volts. In someembodiments, storage node SN of the selected bit-cell SNx is prechargedvia BL and then floated. Here, “floating” means that there is no activedriver for the node. In this case, the precharged voltage value acts asthe initial bias voltage, which can then go down or up depending uponleakage characteristics at that node, or due to ferroelectric capacitorson the SNx node interacting with the read mechanism associated with PLpulsing. In some embodiments, SLx is precharged to a certain voltage ora programmable voltage Vpch. SLx is then driven to a high impedancestate Z.

At that point the PL for the desired FE capacitor is toggled, whichresults into voltage buildup on the SNx node. The voltage build-up onthe SNx node may be different voltage levels depending upon whether theFE capacitor state was logic 0 or logic 1. Due to different voltagelevels on the SNx node, the gain transistor MTR₁ may have differentconduction properties, which reduces the voltage levels on the SLx nodeover time with different rates. For example, if SNx node voltage iscorresponding to a logic 0 state, the conductance of the gain transistorMTR₁ could be lower, and SLx voltage may decay slowly. For a logic 1state, the conductance of the gain transistor MTR₁ could be higher andmay result into the SLx voltage going down faster. The time-sampling ofthis voltage relative to a reference expected value, results indetection of the state in which the FE capacitor was programmed Afterreading the value, a write-back operation can be done to get the valuerestored to the FE capacitor, as reads are destructive reads in thisconfiguration, in accordance with some embodiments.

In the write back process, the selected bit-cell BL (e.g., BLx) ischarged to Vdd or set to 0V depending upon whether a logic 1 or a logic0 is written back to the selected bit-cell. The value written back tothe bit-cell is the same value that the sense amplifier detects whenreading the voltage on the BL. The write back mechanism is like thewrite operation described with reference to FIG. 11C. Here, here, ‘x’ inPLx_n indicates the same orientation as WL. For example, plate-linesPL0_1, PL0_2, and PL0_3 are parallel to WL0. Likewise, plate-linesPL1_1, PL1_2, and PL1_3 are parallel to WL1, and so on.

FIG. 12A illustrates a 3D view of a 1T1C FE bit-cell 1200 with theplate-line parallel to the word-line, where the transistor is a planartransistor and where the capacitor is a planar capacitor, where thebit-line is at a lower metal level than the plate-line, in accordancewith some embodiments. 1T1C FE bit-cell 1200 is similar as 1T1C FEbit-cell 300 but with WL 1217 parallel to PL metal layer 315. In someembodiments, BL 1210 is orthogonal to WL 1217. In some embodiments, BL1210 is replaced with BL 310, which is parallel to PL metal layer 315and WL 1217.

FIG. 12B illustrates a 3D view of 1T1C FE bit-cell 1220 with the PLparallel to the WL, where the transistor is a planar transistor andwhere the capacitor is a planar capacitor with partial encapsulation,where the bit-line is at a lower metal level than the plate-line, inaccordance with some embodiments. 1T1C FE bit-cell 1220 is like 1T1C FEbit-cell 320 but with WL 1217 parallel to PL metal layer 315. In someembodiments, BL 1210 is orthogonal to WL 1217. In some embodiments, BL1210 is replaced with BL 310, which is parallel to PL metal layer 315and WL 1217.

FIG. 12C illustrates a 3D view of 1T1C FE bit-cell 1230 with the PLparallel to the WL, where the transistor is a planar transistor andwhere the capacitor is a planar capacitor with full encapsulation, wherethe bit-line is at a lower metal level than the plate-line, inaccordance with some embodiments. 1T1C FE bit-cell 1230 is like 1T1C FEbit-cell 330 but with WL 1217 parallel to PL metal layer 315. In someembodiments, BL 1210 is orthogonal to WL 1217. In some embodiments, BL1210 is replaced with BL 310, which is parallel to PL metal layer 315and WL 1217.

FIG. 12D illustrates a 3D view of 1T1C FE bit-cell 1240 with theplate-line parallel to the word-line, where the transistor is anon-planar transistor and where the capacitor is a planar capacitor,where the bit-line is at a lower metal level than the plate-line, inaccordance with some embodiments. 1T1C FE bit-cell 1240 is similar as1T1C FE bit-cell 340 but with WL 1217 parallel to PL metal layer 315. Insome embodiments, BL 1210 is orthogonal to WL 1217. In some embodiments,BL 1210 is replaced with BL 310, which is parallel to PL metal layer 315and WL 1217.

FIG. 12E illustrates a 3D view of a 1T1C FE bit-cell 1250 with the PLparallel to the WL, where the transistor is a non-planar transistor andwhere the capacitor is a planar capacitor with partial encapsulation,where the bit-line is at a lower metal level than the plate-line, inaccordance with some embodiments. 1T1C FE bit-cell 1250 is like 1T1C FEbit-cell 350 but with WL 1217 parallel to PL metal layer 315. In someembodiments, BL 1210 is orthogonal to WL 1217. In some embodiments, BL1210 is replaced with BL 310, which is parallel to PL metal layer 315and WL 1217.

FIG. 12F illustrates 3D view of a 1T1C FE bit-cell 1260 with the PLparallel to the WL, where the transistor is a non-planar transistor andwhere the capacitor is a planar capacitor with full encapsulation, wherethe bit-line is at a lower metal level than the plate-line, inaccordance with some embodiments. 1T1C FE bit-cell 1260 is like 1T1C FEbit-cell 360 but with WL 1217 parallel to PL metal layer 315. In someembodiments, BL 1210 is orthogonal to WL 1217. In some embodiments, BL1210 is replaced with BL 310, which is parallel to PL metal layer 315and WL 1217.

FIG. 13A illustrates 3D view of a 1T1C FE bit-cell 1300 with the PLparallel to the WL, where the transistor is a planar transistor andwhere the capacitor is a non-planar capacitor, where the bit-line is ata higher metal level than the plate-line, in accordance with someembodiments. 1T1C FE bit-cell 1300 is like 1T1C FE bit-cell 420 but withWL 1217 parallel to PL metal layer 315. In some embodiments, BL 1210 isorthogonal to WL 1217. In some embodiments, BL 1210 is replaced with BL310, which is parallel to PL metal layer 315 and WL 1217.

FIG. 13B illustrates 3D view of a 1T1C FE bit-cell 1320 with the PLparallel to the WL, where the transistor is a non-planar transistor andwhere the capacitor is a non-planar capacitor, where the bit-line is ata higher metal level than the plate-line, in accordance with someembodiments. 1T1C FE bit-cell 1320 is like 1T1C FE bit-cell 440 but withWL 1217 parallel to PL metal layer 315. In some embodiments, BL 1210 isorthogonal to WL 1217. In some embodiments, BL 1210 is replaced with BL310, which is parallel to PL metal layer 315 and WL 1217.

FIG. 14A illustrates apparatus 1400 comprising memory and correspondinglogic, wherein the memory comprises FE memory bit-cells, where anindividual memory bit-cell is 1TnC bit-cell with plate-lines parallel toa word-line, where the corresponding logic is to apply word-lineboosting, in accordance with some embodiments. Apparatus 1400 is likeapparatus 600 of FIG. 6B but for WL parallel to PLs. In someembodiments, each memory bit-cell in memory array 1401 is organized inrows and columns like in apparatus 600. For example, memory bit-cells1401 _(0,0) through 1401 _(M,N) are organized in an array. Like in FIG.10A, where WL is parallel to PL, PL drivers and WL drivers are lumped inlogic 1004 orthogonal to BL drivers in logic circuitry 203, inaccordance with some embodiments.

FIG. 14B illustrates apparatus 1420 having FE memory with word-linerepeaters, wherein memory arrays of the FE memory having 1TnC bit-cellswith the plate-lines parallel to the word-line, in accordance with someembodiments. Apparatus 1420 illustrates two instances of apparatus 1400.The two instances include first memory array 1401-1, logic circuitry202-1 having first address decoder and/or WL driver, logic circuitry1003-1 having first sense amplifier and BL driver, logic circuitry1404-1 having PL and WL repeaters; second memory array 1401-2, logiccircuitry 202-2 having first address decoder and/or WL driver, logiccircuitry 1003-2 having first sense amplifier and BL driver, and logiccircuitry 1404-2 having PL and WL repeaters. In some embodiments, anindividual instance of apparatus 1400 includes a correspondingwear-leveling logic 206 (e.g., wear-leveling logic 206-1 andwear-leveling logic 206-2). In some embodiments, when the pulsing schemedescribed herein is combined with the refresh function by wear-levelinglogic 206-1 and wear-leveling logic 206-2, disturbance issues onunselected bit-cells are mitigated. While two memory arrays are shown(e.g., memory arrays 1401-1 and 1401-2), any number of arrays may bepart of apparatus 1420. With PL parallel to the WL and orthogonal tologic circuitries 1404-1, 1404-2 etc. having BL, PL and WL repeaters areadded to improve the driving strength of the plate-line signals and theword-line signals. In some embodiments, BL repeaters operate on Vddsupply while WL repeaters operate on a higher power supply level (e.g.,Vdd+Vboost) to implement WL boosting.

FIG. 14C illustrates timing diagram 1430 for write operation for 1TnCbit-cells with plate-line parallel to the word-line, where the writeoperation involves word-line boosting, in accordance with someembodiments. In this case, PLs are parallel to the WL. Depending onwhether logic 1 (Write 1) or logic 0 (Write 0) is being written to theselected capacitor with non-linear polar material, BL, or PL (e.g., BLxand PL0_1) associated with that capacitor of the bit-cell (e.g., 1401_(0,0)) is asserted from 0V to Vdd (power supply level). Other WLs orPLs not part of the bit-cell are forced to 0V. In some embodiments,other PLs (e.g., PL0_2, PL0_3, . . . PL0_n) of the selected bit-cell(e.g., 1401 _(0,0)) are set between 0 and Vdd (e.g., Vdd/2). In someembodiments, PL of the unselected bit-cells (e.g., PL1_0, . . . PL1_n toPLm_0, . . . PLm_n) are set to 0V. In some embodiments, the WLs for theunselected bit-cells (e.g., WL1, WL2, . . . WLm) are set to 0V.

In various embodiments, write operation begins when WL is asserted andboosted above Vdd. The boost level is Vboost which may be 10-50% of Vdd.In one example, Vboost is about 1× to 1.5× of a threshold voltage (Vt)of transistor MN of the 1T1C bit-cell. Since, the select transistor inthese configurations is an n-channel device, it is good at passing the0V and signals closer to it. The signal applied through the BL however,when it is at Vdd, may not pass through the transistor MN₁ incompleteness. As such, there is a Vt drop across the n-type transistorMN₁ if the WL is driven to Vdd. To help get the full range of signalingacross the FE capacitor Cfe1, WL-boosting helps negate the Vt dropacross the transistor such that BL when driven to Vdd, internal nodewill also see Vdd, as opposed to Vdd−Vt.

For the bit-cell topology with PL parallel to the WL, the word-lineboosting is used as otherwise it can lead to a buildup of a voltagelevel of approximately 2× Vdd on the storage node sn1, when BL line isat Vdd, and PL goes from 0V to Vdd. Since, with WL at Vdd, thetransistor MN₁ can be off with BL at Vdd, the storage node sn1 will sitat Vdd−Vt when PL is at 0V. After that when PL goes from 0V to Vdd, theinternal node can jump to 2Vdd−Vt level. When WL is voltage boosted, andthe PL voltage rises from 0V to Vdd, the storage node or internal nodemay not see the voltage spike, as the transistor MN₁ may still be in theon condition. This helps with the reliability aspect of the transistorMN₁. Note, a large voltage buildup on the storage node or internal nodeof the transistor can cause lifetime degradation and correspondinglyyield issues.

When a particular bit-cell (e.g., 1401 _(0,0)) is being written to, theWL for unselected bit-cells (e.g., WL0 through WLm) remains at 0. Sameis done for unselected PLs as illustrated. Timing diagram 1430 is afirst order diagram without column multiplexing. A person skilled in theart would appreciate that column multiplexing is used for accessingmemory bit-cells in an array. Here. all BLs within an active array aretoggled according to what is being written. Since the BLs are orthogonalto the WL, and PL is being toggled, BLs are driven either 0 or 1,depending on what is being written. In some embodiments, when columnmultiplexing is implemented, the corresponding BL lines of inactivebit-cells are set to Vdd/2 to minimize the disturb effect on thosebit-cells. Column multiplexing may reduce an overhead of the peripheralcircuitry (not shown). In some embodiments, column multiplexing may notbe used to avoid any disturb effect on unselected bit-cells.

In various embodiments, the BL and PL for the selected bit-cellcapacitor are asserted and de-asserted within a pulse width of theboosted WL. In some embodiments, the voltage swing for BL and PL isbetween 0 to Vdd. In some embodiments, the selected PL (PL1_0) isasserted and de-asserted within the pulse width of BLx (e.g., BL0). Insome embodiments, unselected PLs of the selected bit-cells are parked ata lower voltage (e.g., Vdd/2) to limit the disturb effect on thosecapacitors due to voltage on the internal node sn1 being either Vdd or0. This limits the disturbance as seen by other ferroelectric capacitorsof the selected bit-cells. The pulse width of the unselected PLs (e.g.,PL0_2, PL0_3, . . . PL0_n), of the selected bit-cell is substantiallythe same as the pulse width of the boosted WL (e.g., WL0), in accordancewith some embodiments.

In some embodiments, the BL or PL pulse is generated after apredetermined or programmable time from when WL boost starts, and the BLor PL pulse ends within the WL pulse. In one example, to write a logic 1to all capacitors Cfe1 through Cfen, BL pulse is generated within thepulse width of the boosted WL. All other PLs for the unselected bit-cellare set to 0V (e.g., PL1_1, PL1_2, through PL1_n are forced to 0V, andlikewise PL2_1, PL2_2, through PL2_n are forced to 0V, and so on).

PLs (e.g., PL0_2 through n) within the same selected bit-cell (e.g.,1401 _(0,0)) are charged to Vdd/2, in accordance with variousembodiments. In some embodiments, PL for unselected bit-cells remains at0V while PL0_1 is being used to program Cfe1. Word-lines of unselectedbit-cells are set to 0V (e.g., WL1, 2, through M are set to 0V when WL0is selected).

FIG. 14D illustrates timing diagram 1440 for read operation 1TnCbit-cells with plate-line parallel to the word-line, where the readoperation involves word-line boosting, in accordance with someembodiments. In some embodiments, the selected WL is boosted for readoperation. WL is boosted above Vdd to Vdd+Vboost level. In someembodiments, a writeback scheme is implemented after the read operationto restore the data value stored in the selected bit-cell due to thedestructive nature of the read operation. In one such embodiment, thedata which is read is also written back in the writeback time windowafter the read time window. In some embodiments, PL is asserted for thebit-cell which is being read.

In some embodiments, PL for the selected capacitor of the bit-cell isasserted for a time period long enough for the sense amplifier to sensethe value stored on the storage node coupled to the capacitor. Invarious embodiments, sense amplifier enable signal (SAE) is assertedwithin the pulse width of the PL. In some embodiments, to read data fromthe storage node, BL is set or forced to zero volts. In someembodiments, storage node SN of the selected bit-cell SNx is prechargedvia BL and then floated. Here, “floating” means that there is no activedriver for the node. In this case, the precharged voltage value acts asthe initial bias voltage, which can then go down or up depending uponleakage characteristics at that node, or due to ferroelectric capacitorson the SNx node interacting with the read mechanism associated with PLpulsing. In some embodiments, SLx is precharged to a certain voltage ora programmable voltage Vpch. SLx is then driven to a high impedancestate Z.

At that point the PL for the desired FE capacitor is toggled, whichresults into voltage buildup on the SNx node. The voltage build-up onthe SNx node may be different voltage levels depending upon whether theFE capacitor state was logic 0 or logic 1. The time-sampling of thisvoltage relative to a reference expected value, results in detection ofthe state in which the FE capacitor was programmed After reading thevalue, a write-back operation can be done to get the value restored tothe FE capacitor, as reads are destructive read in this configuration,in accordance with some embodiments.

In the write back process, the selected bit-cell BL (e.g., BLx) ischarged to Vdd or set to 0V depending upon whether a logic 1 or a logic0 is written back to the selected bit-cell. The value written back tothe bit-cell is the same value that the sense amplifier detects whenreading the voltage on the BL. The write back mechanism is like thewrite operation described with reference to FIG. 14C. Here, here, ‘x’ inPLx_n indicates the same orientation as WL. For example, plate-linesPL0_1, PL0_2, and PL0_3 are parallel to WL0. Likewise, plate-linesPL1_1, PL1_2, and PL1_3 are parallel to WL1, and so on.

While various embodiments are described with reference to selecttransistors as being n-type transistors, the n-type transistors may bereplaced with p-type transistors. In one such case, the logic associatedwith the transistors may be modified to achieve the correct polarity ofthe signals for proper function of the bit-cells.

Various embodiments illustrates the read mechanism where the BL isprecharged to a 0V signal, and the PL across the FE capacitor is pulsedfrom 0 to Vdd and back to 0V resulting into a sense-signal with respectto having written a 0 state to the FE capacitor (voltage on the BL minusthe voltage on the PL being −Ve). The sense-signal on the sense-linecorresponds to whether the bit-cell was holding a prior state of 0(same-state) or 1 (opposite state). In some embodiments, the scheme forread can be changed such that the BL is precharged to Vdd instead, andthe PL is held at 0V. In this case, at the end of the precharge phase,the selected bit-cell may create a signal on the BL that will correspondto the bit-cell being written a logic 1 state instead (voltage on the BLminus the voltage on the PL being +ve). The sense-signal as generated onthe BL in this case may still correspond to as if the bit-cell washolding a prior state of 0 (opposite-state) or 1 (same-state), with thevoltage on BL changing from its precharged state by higher amount whenit's an opposite state. This scheme can have the potential for bettersense-margin, as the PL switching may not happen during the sense-phase,avoiding any potential coupling related sense-margin reduction. Thescheme is also helpful for avoiding read disturbance due to the PLtoggles on the bit-cells. Particularly in configurations where theunselected bit-cells can be exposed to the PL toggle, the scheme avoidscoupling on the BL, as PL may not have to toggle.

In some embodiments, the way the cells are read can be periodicallychanged. For example, with the same state being 1 (write 1 during read,i.e., BL is precharged high, while keeping PL low), or same state being0 (write 0 during read, i.e., BL is precharged low, and PL is toggledhigh) during the read phase. This can be done to improve the retentioncharacteristics for the cells, as monotonic continuous reads requiringwrites of the same polarity can hurt the disturb-induced effect on otherbit-cells which gets negated due to the periodic inversion of the waythe reads are done. This also can improve the artefact of imprintphenomenon, since a bit-cell even if it is holding a particular state,it may not continuously get written the same value since the readmechanism diversifies it between a read with same state or oppositestate, thereby lowering imprint effects with the memory cell.

FIG. 15 illustrates a high-level architecture of an artificialintelligence (AI) machine comprising a compute die stacked with a memorydie, wherein the compute die includes any one of the memoryarchitectures and associated read/write scheme, in accordance with someembodiments. AI machine 1500 comprises computational block 1501 orprocessor having random-access memory (RAM) 1502 and computational logic1503; first random-access memory (RAM) 1504 (e.g., static RAM (SRAM),ferroelectric or paraelectric RAM (FeRAM), ferroelectric or paraelectricstatic random-access memory (FeSRAM)), main processor 1505, secondrandom-access memory (RAM) 1506 (dynamic RAM (DRAM), FeRAM), andsolid-state memory or drive (SSD) 1507. In some embodiments, some or allcomponents of AI machine 1500 are packaged in a single package forming asystem-on-chip (SoC). The SoC can be configured as a logic-on-logicconfiguration, which can be in a 3D configuration or a 2.5Dconfiguration.

In some embodiments, computational block 1501 is packaged in a singlepackage and then coupled to processor 1505 and memories 1504, 1506, and1507 on a printed circuit board (PCB). In some embodiments,computational block 1501 is configured as a logic-on-logicconfiguration, which can be in a 3D configuration or a 2.5Dconfiguration. In some embodiments, computational block 1501 comprises aspecial purpose compute die 1503 or microprocessor. For example,computational logic (e.g., compute die) 1503 is a compute chiplet thatperforms a function of an accelerator or inference. In some embodiments,RAM 1502 is DRAM which forms a special memory/cache for the specialpurpose compute die 1503. The DRAM can be embedded DRAM (eDRAM) such as1T1C (one transistor and one capacitor) based memories. In someembodiments, RAM 1502 is ferroelectric or paraelectric RAM (Fe-RAM).

In some embodiments, computational logic 1503 is specialized forapplications such as Artificial Intelligence, graph processing, andalgorithms for data processing. In some embodiments, computational logic1503 further has logic computational blocks, for example, formultipliers and buffers, a special data memory block (e.g., buffers)comprising DRAM, FeRAM, or a combination of them. In some embodiments,RAM 1502 has weights and inputs stored to improve the computationalefficiency. The interconnects between processor 1505 (also referred toas special purpose processor), first RAM 1504 and computational logic1503 are optimized for high bandwidth and low latency. The architectureof FIG. 15 allows efficient packaging to lower the energy, power, orcost and provides for ultra-high bandwidth between RAM 1502 andcomputational logic 1503 of computational block 1501.

In some embodiments, RAM 1502 is partitioned to store input data (ordata to be processed) 1502 a and weight factors 1502 b. In someembodiments, input data 1502 a is stored in a separate memory (e.g., aseparate memory die) and weight factors 1502 b are stored in a separatememory (e.g., separate memory die).

In some embodiments, computational logic or compute chiplet 1503comprises matrix multiplier, adder, concatenation logic, buffers, andcombinational logic. In various embodiments, computational logic (e.g.,compute chiplet) 1503 performs multiplication operation on input data1502 a and weight factors 1502 b. In some embodiments, weight factors1502 b are fixed weights. For example, processor 1505 (e.g., a graphicsprocessor unit (GPU), field programmable grid array (FPGA) processor,application specific integrated circuit (ASIC) processor, digital signalprocessor (DSP), an AI processor, a central processing unit (CPU), orany other high-performance processor) computes the weights for atraining model. Once the weights are computed, they are stored in RAM1502. In various embodiments, the input data that is to be analyzedusing a trained model, is processed by computational block 1501 withcomputed weight factors 1502 b to generate an output (e.g., aclassification result).

In some embodiments, first RAM 1504 is ferroelectric or paraelectricbased SRAM. For example, a six transistor (6T) SRAM bit-cells havingferroelectric or paraelectric transistors are used to implement anon-volatile FeSRAM. In some embodiments, SSD 1507 comprises NAND flashcells. In some embodiments, SSD 1507 comprises NOR flash cells. In someembodiments, SSD 1507 comprises multi-threshold NAND flash cells.

In various embodiments, the non-volatility of FeRAM is used to introducenew features such as security, functional safety, and faster reboot timeof AI machine 1500. The non-volatile FeRAM is a low power RAM thatprovides fast access to data and weights. FeRAM 1504 can also serve as afast storage for computational block 1501 (which can be an inference dieor an accelerator), which typically has low capacity and fast accessrequirements.

In various embodiments, the FeRAM (FeDRAM or FeSRAM) includesferroelectric or paraelectric material. The ferroelectric orparaelectric (FE) material may be in a transistor gate stack or in acapacitor of the memory. The ferroelectric material can be any suitablelow voltage FE material discussed with reference to various embodiments.While embodiments here are described with reference to ferroelectricmaterial, the embodiments are applicable to any of the non-linear polarmaterials described herein.

FIG. 16 illustrates an architecture of a computational block 1600comprising a compute die stacked with a memory die, wherein the computedie includes any one of the memory architectures and associatedread/write scheme, in accordance with some embodiments. Any of theblocks here can include the bit-cell of various embodiments. Thearchitecture of FIG. 16 illustrates an architecture for a specialpurpose compute die where RAM memory buffers for inputs and weights aresplit on die-1 and logic and optional memory buffers are split on die-2.

In some embodiments, memory die (e.g., Die 1) is positioned belowcompute die (e.g., Die 2) such that heat sink or thermal solution isadjacent to the compute die. In some embodiments, the memory die isembedded in an interposer. In some embodiments, the memory die behavesas an interposer in addition to its basic memory function. In someembodiments, the memory die is a high bandwidth memory (HBM) whichcomprises multiple dies of memories in a stack and a controller tocontrol the read and write functions to the stack of memory dies. Insome embodiments, the memory die comprises a first die comprising memory1601 to store input data and a second die comprising memory 1602 tostore weight factors. In some embodiments, the memory die is a singledie that is partitioned such that first partition or memory 1601 of thememory die is used to store input data and second partition or memory1602 of the memory die is used to store weights. In some embodiments,the memory die comprises DRAM. In some embodiments, the memory diecomprises FE-SRAM or FE-DRAM. In some embodiments, the memory diecomprises MRAM. In some embodiments, the memory die comprises SRAM. Forexample, memory partitions 1601 and 1602, or memory dies 1601 and 1602include one or more of: DRAM, FE-SRAM, FE-DRAM, SRAM, and/or MRAM. Insome embodiments, the input data stored in memory partition or die 1601is the data to be analyzed by a trained model with fixed weights storedin memory partition or die 1602.

In some embodiments, the compute die comprises ferroelectric orparaelectric logic (e.g., majority, minority, and/or threshold gates) toimplement matrix multiplier 1603, logic 1604, and temporary buffer 1605.Matrix multiplier 1603 performs multiplication operation on input data‘X’ and weights ‘W’ to generate an output ‘Y’. This output may befurther processed by logic 1604. In some embodiments, logic 1604performs a threshold operation, pooling and drop out operations, and/orconcatenation operations to complete the AI logic primitive functions.

In some embodiments, the output of logic 1604 (e.g., processed output‘Y’) is temporarily stored in buffer 1605. In some embodiments, buffer1605 is memory such as one or more of: DRAM, Fe-SRAM, Fe-DRAM, MRAM,resistive RAM (Re-RAM) and/or SRAM. In some embodiments, buffer 1605 ispart of the memory die (e.g., Die 1). In some embodiments, buffer 1605performs the function of a re-timer. In some embodiments, the output ofbuffer 1605 (e.g., processed output ‘Y’) is used to modify the weightsin memory partition or die 1602. In one such embodiment, computationalblock 1600 not only operates as an inference circuitry, but also as atraining circuitry to train a model. In some embodiments, matrixmultiplier 1603 includes an array of multiplier cells, wherein the DRAMs1601 and 1602 include arrays of memory bit-cells, respectively, whereineach multiplier cell is coupled to a corresponding memory bit-cell ofDRAM 1601 and/or DRAM 1602. In some embodiments, computational block1600 comprises an interconnect fabric coupled to the array of multipliercells such that each multiplier cell is coupled to the interconnectfabric.

Computational block 1600 provides reduced memory access for the computedie (e.g., die 2) by providing data locality for weights, inputs, andoutputs. In one example, data from and to the AI computational blocks(e.g., matrix multiplier 1603) is locally processed within a samepackaging unit. Computational block 1600 also segregates the memory andlogic operations onto a memory die (e.g., Die 1) and a logic die (e.g.,Die 2), respectively, allowing for optimized AI processing. Desegregateddies allow for improved yield of the dies. A high-capacity memoryprocess for Die 1 allows reduction of power of the externalinterconnects to memory, reduces cost of integration, and results in asmaller footprint.

FIG. 17 illustrates a system-on-chip (SOC) 1700 that uses any one of thememory architectures and associated read/write scheme, in accordancewith some embodiments. SoC 1700 comprises memory 1701 having staticrandom-access memory (SRAM) or FE based random-access memory FE-RAM, orany other suitable memory. The memory can be non-volatile (NV) orvolatile memory. Memory 1701 may also comprise logic 1703 to controlmemory 1702. For example, write and read drivers are part of logic 1703.These drivers and other logic are implemented using the majority orthreshold gates of various embodiments. The logic can comprise majorityor threshold gates and traditional logic (e.g., CMOS based NAND, NORetc.).

SoC further comprises a memory I/O (input-output) interface 1704. Theinterface may be double-data rate (DDR) compliant interface or any othersuitable interface to communicate with a processor. Processor 1705 ofSoC 1700 can be a single core or multiple core processor. Processor 1705can be a general-purpose processor (CPU), a digital signal processor(DSP), or an Application Specific Integrated Circuit (ASIC) processor.In some embodiments, processor 1705 is an artificial intelligence (AI)processor (e.g., a dedicated AI processor, a graphics processorconfigured as an AI processor). In various embodiments, processor 1705executes instructions that are stored in memory 1701.

AI is a broad area of hardware and software computations where data isanalyzed, classified, and then a decision is made regarding the data.For example, a model describing classification of data for a certainproperty or properties is trained over time with large amounts of data.The process of training a model requires large amounts of data andprocessing power to analyze the data. When a model is trained, weightsor weight factors are modified based on outputs of the model. Onceweights for a model are computed to a high confidence level (e.g., 95%or more) by repeatedly analyzing data and modifying weights to get theexpected results, the model is deemed “trained.” This trained model withfixed weights is then used to make decisions about new data. Training amodel and then applying the trained model for new data is hardwareintensive activity. In some embodiments, the AI processor has reducedlatency of computing the training model and using the training model,which reduces the power consumption of such AI processor systems.

Processor 1705 may be coupled to a number of other chip-lets that can beon the same die as SoC 1700 or on separate dies. These chip-lets includeconnectivity circuitry 1706, I/O controller 1707, power management 1708,and display system 1709, and peripheral connectivity circuitry 1706.

Connectivity circuitry 1706 represents hardware devices and softwarecomponents for communicating with other devices. Connectivity circuitry1706 may support various connectivity circuitries and standards. Forexample, connectivity circuitry 1706 may support GSM (global system formobile communications) or variations or derivatives, CDMA (code divisionmultiple access) or variations or derivatives, TDM (time divisionmultiplexing) or variations or derivatives, 3rd Generation PartnershipProject (3GPP) Universal Mobile Telecommunications Systems (UMTS) systemor variations or derivatives, 3GPP Long-Term Evolution (LTE) system orvariations or derivatives, 3GPP LTE-Advanced (LTE-A) system orvariations or derivatives, Fifth Generation (5G) wireless system orvariations or derivatives, 5G mobile networks system or variations orderivatives, 5G New Radio (NR) system or variations or derivatives, orother cellular service standards. In some embodiments, connectivitycircuitry 1706 may support non-cellular standards such as WiFi.

I/O controller 1707 represents hardware devices and software componentsrelated to interaction with a user. I/O controller 1707 is operable tomanage hardware that is part of an audio subsystem and/or displaysubsystem. For example, input through a microphone or other audio devicecan provide input or commands for one or more applications or functionsof SoC 1700. In some embodiments, I/O controller 1707 illustrates aconnection point for additional devices that connect to SoC 1700 throughwhich a user might interact with the system. For example, devices thatcan be attached to the SoC 1700 might include microphone devices,speaker or stereo systems, video systems or other display devices,keyboard or keypad devices, or other I/O devices for use with specificapplications such as card readers or other devices.

Power management 1708 represents hardware or software that perform powermanagement operations, e.g., based at least in part on receivingmeasurements from power measurement circuitries, temperature measurementcircuitries, charge level of battery, and/or any other appropriateinformation that may be used for power management. By using majority andthreshold gates of various embodiments, non-volatility is achieved atthe output of these logic. Power management 1708 may accordingly putsuch logic into low power state without the worry of losing data. Powermanagement may select a power state according to Advanced Configurationand Power Interface (ACPI) specification for one or all components ofSoC 1700.

Display system 1709 represents hardware (e.g., display devices) andsoftware (e.g., drivers) components that provide a visual and/or tactiledisplay for a user to interact with the processor 1705. In someembodiments, display system 1709 includes a touch screen (or touch pad)device that provides both output and input to a user. Display system1709 may include a display interface, which includes the particularscreen or hardware device used to provide a display to a user. In someembodiments, the display interface includes logic separate fromprocessor 1705 to perform at least some processing related to thedisplay.

Peripheral connectivity 1710 may represent hardware devices and/orsoftware devices for connecting to peripheral devices such as printers,chargers, cameras, etc. In some embodiments, peripheral connectivity1710 may support communication protocols, e.g., PCIe (PeripheralComponent Interconnect Express), USB (Universal Serial Bus),Thunderbolt, High-Definition Multimedia Interface (HDMI), Firewire, etc.

In various embodiments, SoC 1700 includes a coherent cache ormemory-side buffer chiplet (not shown) which include ferroelectric orparaelectric memory. The coherent cache or memory-side buffer chipletcan be coupled to processor 1705 and/or memory 1701 according to thevarious embodiments described herein (e.g., via silicon bridge orvertical stacking).

FIG. 18 illustrates a cross-sectional view 1800 of bit-cells withstacked planar non-linear polar material based capacitors, in accordancewith some embodiments. In this example, four transistors are shown, eachcontrolled by its respective WL on its gate terminal. The source anddrain terminals of each transistor is coupled to respective contacts(CA). A pair of transistors are grouped together and separated fromother pairs via isolation region. Etch stop layer is used in thefabrication of vias (via0) to connect the source and drain of thetransistors to BLs on metal-1 (M1) layer. Another etch stop layer isformed over M1 layer to fabricate vias (via1) to couple to respective M1layers. In some embodiments, metal-2 (M2) is deposited over vias (via1).M2 layer is then polished. In some embodiments, the capacitor can bemoved further up in the stack, where the capacitor level processing isdone between different layers. In some embodiments, BL can be escaped ona different layer than shown. Here, bit-cell 1801 _(0,0) illustrate one1TnC bit-cell with planar stacked capacitors capacitor.

In some embodiments, oxide is deposited over the etch stop layer.Thereafter, dry, or wet etching is performed to form holes forpedestals. The holes are filled with metal and land on the respective M2layers. Fabrication processes such as interlayer dielectric (ILD) oxidedeposition followed by ILD etch (to form holes for the pedestals),deposition of metal into the holes, and subsequent polishing of thesurface are used to prepare for post pedestal fabrication.

A number of fabrication processes of deposition, lithography, andetching takes place to form the stack of layers for the planarcapacitor. In some embodiments, the planar ferroelectric or paraelectriccapacitors are formed in a backend of the die. In some embodiments,deposition of ILD is followed by surface polish. In some embodiments, PLis formed over top electrode of each capacitor. In this case, afterpolishing the surface, ILD is deposited, in accordance with someembodiments. Thereafter, holes are etched through the ILD to expose thetop electrodes of the capacitors, in accordance with some embodiments.The holes are then filled with metal, in accordance with someembodiments. Followed by filling the holes, the top surface is polished,in accordance with some embodiments. As such, the capacitors areconnected to PL and storage nodes (through the pedestals), in accordancewith some embodiments.

In some embodiments, ILD is deposited over the polished surface. Holesfor via are then etched to contact the M2 layer, in accordance with someembodiments. The holes are filled with metal to form vias (via2), inaccordance with some embodiments. The top surface is then polished, inaccordance with some embodiments. In some embodiments, process ofdepositing metal over the vias (via2), depositing ILD, etching holes toform pedestals for the next capacitors of the stack, forming thecapacitors, and then forming vias that contact the M3 layer arerepeated. This process is repeated ‘n’ times for forming ‘n’ capacitorsin a stack, in accordance with some embodiments. In some embodiments,one terminal of a capacitor is coupled to the storage node (e.g., sn1)and the other terminal of the capacitor is coupled to a PL.

In some embodiments, the bottom electrode of each capacitor is allowedto directly contact with the metal below. In this embodiment, the heightof the stacked capacitors is lowered, and the fabrication process issimplified because the extra steps for forming the pedestals areremoved.

In some embodiments, pedestals or vias are formed for both the top andbottom electrodes of the non-linear polar material based capacitorand/or the Cd capacitor. In this embodiment, the height of the stackedcapacitors is raised, and the fabrication process adds an additionalstep of forming a top pedestal or via which contacts with a respectivePL. In some embodiments, a similar structure of stacked capacitors canbe used for the multi-element gain memory bit-cell.

FIG. 19 illustrates cross-sectional view 1900 of bit-cells with stackednon-planar non-linear polar material based capacitors, in accordancewith some embodiments. In this example four 1TnC bit-cells are shown,where ‘n’ is three. Each group of capacitors for a bit-cell (e.g., 1901_(0,0)) has a column of shared metal passing through the center of thecapacitors, where the shared metal is the storage node which is coupledto the stub and then to the source or drain terminal. Top electrode ofeach of the capacitor is partially adjacent to a respective plate-line.In this instance, the capacitors are formed between regions reserved forVia1 through Via5 (e.g., between M1 through M6 layers). In someembodiments, a similar structure of stacked capacitors can be used forthe multi-element gain memory bit-cell.

The term “device” may generally refer to an apparatus according to thecontext of the usage of that term. For example, a device may refer to astack of layers or structures, a single structure or layer, a connectionof various structures having active and/or passive elements, etc.Generally, a device is a three-dimensional structure with a plane alongthe x-y direction and a height along the z direction of an x-y-zCartesian coordinate system. The plane of the device may also be theplane of an apparatus, which comprises the device.

Throughout the specification, and in the claims, the term “connected”means a direct connection, such as electrical, mechanical, or magneticconnection between the things that are connected, without anyintermediary devices.

The term “coupled” means a direct or indirect connection, such as adirect electrical, mechanical, or magnetic connection between the thingsthat are connected or an indirect connection, through one or morepassive or active intermediary devices.

The term “adjacent” here generally refers to a position of a thing beingnext to (e.g., immediately next to or close to with one or more thingsbetween them) or adjoining another thing (e.g., abutting it).

The term “circuit” or “module” may refer to one or more passive and/oractive components that are arranged to cooperate with one another toprovide a desired function.

The term “signal” may refer to at least one current signal, voltagesignal, magnetic signal, or data/clock signal. The meaning of “a,” “an,”and “the” include plural references. The meaning of “in” includes “in”and “on.”

Here, the term “analog signal” generally refers to any continuous signalfor which the time varying feature (variable) of the signal is arepresentation of some other time varying quantity, i.e., analogous toanother time varying signal.

Here, the term “digital signal” generally refers to a physical signalthat is a representation of a sequence of discrete values (a quantifieddiscrete-time signal), for example of an arbitrary bit stream, or of adigitized (sampled and analog-to-digital converted) analog signal.

The term “scaling” generally refers to converting a design (schematicand layout) from one process technology to another process technologyand subsequently being reduced in layout area. The term “scaling”generally also refers to downsizing layout and devices within the sametechnology node. The term “scaling” may also refer to adjusting (e.g.,slowing down or speeding up—i.e., scaling down, or scaling uprespectively) of a signal frequency relative to another parameter, forexample, power supply level.

The terms “substantially,” “close,” “approximately,” “near,” and“about,” generally refer to being within +/−10% of a target value. Forexample, unless otherwise specified in the explicit context of theiruse, the terms “substantially equal,” “about equal” and “approximatelyequal” mean that there is no more than incidental variation betweenamong things so described. In the art, such variation is typically nomore than +1-10% of a predetermined target value.

Unless otherwise specified the use of the ordinal adjectives “first,”“second,” and “third,” etc., to describe a common object, merelyindicate that different instances of like objects are being referred toand are not intended to imply that the objects so described must be in agiven sequence, either temporally, spatially, in ranking or in any othermanner.

For the purposes of the present disclosure, phrases “A and/or B” and “Aor B” mean (A), (B), or (A and B). For the purposes of the presentdisclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B),(A and C), (B and C), or (A, B and C).

The terms “left,” “right,” “front,” “back,” “top,” “bottom,” “over,”“under,” and the like in the description and in the claims, if any, areused for descriptive purposes and not necessarily for describingpermanent relative positions. For example, the terms “over,” “under,”“front side,” “back side,” “top,” “bottom,” “over,” “under,” and “on” asused herein refer to a relative position of one component, structure, ormaterial with respect to other referenced components, structures ormaterials within a device, where such physical relationships arenoteworthy. These terms are employed herein for descriptive purposesonly and predominantly within the context of a device z-axis andtherefore may be relative to an orientation of a device. Hence, a firstmaterial “over” a second material in the context of a figure providedherein may also be “under” the second material if the device is orientedupside-down relative to the context of the figure provided. In thecontext of materials, one material disposed over or under another may bedirectly in contact or may have one or more intervening materials.Moreover, one material disposed between two materials may be directly incontact with the two layers or may have one or more intervening layers.In contrast, a first material “on” a second material is in directcontact with that second material. Similar distinctions are to be madein the context of component assemblies.

The term “between” may be employed in the context of the z-axis, x-axisor y-axis of a device. A material that is between two other materialsmay be in contact with one or both of those materials, or it may beseparated from both of the other two materials by one or moreintervening materials. A material “between” two other materials maytherefore be in contact with either of the other two materials, or itmay be coupled to the other two materials through an interveningmaterial. A device that is between two other devices may be directlyconnected to one or both of those devices, or it may be separated fromboth of the other two devices by one or more intervening devices.

Here, multiple non-silicon semiconductor material layers may be stackedwithin a single fin structure. The multiple non-silicon semiconductormaterial layers may include one or more “P-type” layers that aresuitable (e.g., offer higher hole mobility than silicon) for P-typetransistors. The multiple non-silicon semiconductor material layers mayfurther include one or more “N-type” layers that are suitable (e.g.,offer higher electron mobility than silicon) for N-type transistors. Themultiple non-silicon semiconductor material layers may further includeone or more intervening layers separating the N-type from the P-typelayers. The intervening layers may be at least partially sacrificial,for example to allow one or more of a gate, source, or drain to wrapcompletely around a channel region of one or more of the N-type andP-type transistors. The multiple non-silicon semiconductor materiallayers may be fabricated, at least in part, with self-aligned techniquessuch that a stacked CMOS device may include both a high-mobility N-typeand P-type transistor with a footprint of a single FET (field effecttransistor).

Here, the term “backend” generally refers to a section of a die which isopposite of a “frontend” and where an IC (integrated circuit) packagecouples to IC die bumps. For example, high-level metal layers (e.g.,metal layer 6 and above in a ten-metal stack die) and corresponding viasthat are closer to a die package are considered part of the backend ofthe die. Conversely, the term “frontend” generally refers to a sectionof the die that includes the active region (e.g., where transistors arefabricated) and low-level metal layers and corresponding vias that arecloser to the active region (e.g., metal layer 5 and below in theten-metal stack die example).

Reference in the specification to “an embodiment,” “one embodiment,”“some embodiments,” or “other embodiments” means that a particularfeature, structure, or characteristic described in connection with theembodiments is included in at least some embodiments, but notnecessarily all embodiments. The various appearances of “an embodiment,”“one embodiment,” or “some embodiments” are not necessarily allreferring to the same embodiments. If the specification states acomponent, feature, structure, or characteristic “may,” “might,” or“could” be included, that particular component, feature, structure, orcharacteristic is not required to be included. If the specification orclaim refers to “a” or “an” element, that does not mean there is onlyone of the elements. If the specification or claims refer to “anadditional” element, that does not preclude there being more than one ofthe additional elements.

Furthermore, the particular features, structures, functions, orcharacteristics may be combined in any suitable manner in one or moreembodiments. For example, a first embodiment may be combined with asecond embodiment anywhere the particular features, structures,functions, or characteristics associated with the two embodiments arenot mutually exclusive.

While the disclosure has been described in conjunction with specificembodiments thereof, many alternatives, modifications and variations ofsuch embodiments will be apparent to those of ordinary skill in the artin light of the foregoing description. The embodiments of the disclosureare intended to embrace all such alternatives, modifications, andvariations as to fall within the broad scope of the appended claims.

In addition, well-known power/ground connections to integrated circuit(IC) chips and other components may or may not be shown within thepresented figures, for simplicity of illustration and discussion, and soas not to obscure the disclosure. Further, arrangements may be shown inblock diagram form to avoid obscuring the disclosure, and also in viewof the fact that specifics with respect to implementation of such blockdiagram arrangements are highly dependent upon the platform within whichthe present disclosure is to be implemented (i.e., such specifics shouldbe well within purview of one skilled in the art). Where specificdetails (e.g., circuits) are set forth to describe example embodimentsof the disclosure, it should be apparent to one skilled in the art thatthe disclosure can be practiced without, or with variation of, thesespecific details. The description is thus to be regarded as illustrativeinstead of limiting.

The structures of various embodiments described herein can also bedescribed as method of forming those structures, and method of operationof these structures.

Following examples are provided that illustrate the various embodiments.The examples can be combined with other examples. As such, variousembodiments can be combined with other embodiments without changing thescope of the invention.

Example 1: An apparatus comprising: a node; a capacitor comprisingnon-linear polar material, the capacitor having a first terminal coupledto the node and a second terminal coupled to a plate-line, wherein thecapacitor is a pillar capacitor; a transistor coupled to the node and abit-line, wherein the transistor is controllable by a word-line, whereinthe plate-line is parallel to the bit-line; a refresh circuitry torefresh charge on the capacitor periodically; and one or morecircuitries to boost the word-line above a voltage supply level during awrite operation and a read operation, wherein the one or morecircuitries is to generate a first pulse on the bit-line after theword-line is boosted and before an end of the boost on the word-lineduring a first write operation, and wherein the one or more circuitriesis to generate a second pulse on the plate-line after the word-line isboosted and before the end of the boost on the word-line during a secondwrite operation different from the first write operation.

Example 2: The apparatus of example 1, wherein the refresh circuitrycomprises logic to improve memory endurance of the capacitor via wearleveling, wherein the wear leveling is applied during read or writeoperations.

Example 3: The apparatus of example 2, wherein the wear levelingincludes a random wear leveling scheme.

Example 4: The apparatus of example 2, the refresh circuitry is to applyan outlier compensation scheme before or after the wear leveling.

Example 5: The apparatus of example 1, wherein the one or morecircuitries is to force a first voltage on the plate-line during thefirst write operation.

Example 6: The apparatus of example 5, wherein the one or morecircuitries is to force the first voltage on the bit-line during thefirst write operation.

Example 7: The apparatus of example 1, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation,wherein the one or more circuitries is to boost the word-line above thevoltage supply level during the read operation.

Example 8: The apparatus of example 7, wherein the one or morecircuitries is to generate a third pulse on the plate-line after theword-line is boosted and before an end of the boost on the word-lineduring the read operation.

Example 9: The apparatus of example 1, wherein the transistor is a lowleakage transistor.

Example 10: The apparatus of example 1 comprising a repeater coupled tothe word-line.

Example 11: The apparatus of example 1, wherein the transistor is afirst transistor, wherein the apparatus comprises a second transistorhaving a gate terminal coupled to the word-line, wherein the secondterminal of the capacitor is coupled to the plate-line via the secondtransistor, wherein a source terminal of the second transistor iscoupled to the plate-line, wherein a drain terminal of the secondtransistor coupled to the second terminal of the capacitor.

Example 12: The apparatus of example 1, wherein when the capacitorcomprises: a first layer comprising a first conducting material, whereinthe first layer is coupled to the first terminal of the capacitor; asecond layer comprising a second conducting material, wherein the secondlayer is around the first layer; a third layer comprising the non-linearpolar material, wherein the third layer is around the second layer; afourth layer comprising the second conducting material, wherein thefourth layer is around the third layer; and a fifth layer comprising thefirst conducting material, wherein the plate-line is partially coupledto the fifth layer.

Example 13: The apparatus of example 12, wherein the first layer has afirst circumference, wherein the second layer has a secondcircumference, wherein the third layer has a third circumference,wherein the fourth layer has a fourth circumference, wherein the fifthlayer has a fifth circumference, wherein the fourth circumference islarger than the third circumference, wherein the third circumference islarger than the second circumference, and wherein the secondcircumference is larger than the first circumference.

Example 14: The apparatus of example 1, wherein the non-linear polarmaterial includes one of: Bismuth ferrite (BFO), BFO with a dopingmaterial where in the doping material is one of Lanthanum, or elementsfrom lanthanide series of periodic table; Lead zirconium titanate (PZT),or PZT with a doping material, wherein the doping material is one of La,Nb; a relaxor ferroelectric which includes one of lead magnesium niobate(PMN), lead magnesium niobate-lead titanate (PMN-PT), lead lanthanumzirconate titanate (PLZT), lead scandium niobate (PSN), BariumTitanium-Bismuth Zinc Niobium Tantalum (BT-BZNT), or BariumTitanium-Barium Strontium Titanium (BT-BST); a perovskite which includesone of: BaTiO3, PbTiO3, KNbO3, or NaTaO3; a hexagonal ferroelectricwhich includes one of: YMnO3, or LuFeO3; hexagonal ferroelectrics of atype h-RMnO3, where R is a rare earth element which includes one of:cerium (Ce), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium(Gd), holmium (Ho), lanthanum (La), lutetium (Lu), neodymium (Nd),praseodymium (Pr), promethium (Pm), samarium (Sm), scandium (Sc),terbium (Tb), thulium (Tm), ytterbium (Yb), or yttrium (Y); Hafnium(Hf), Zirconium (Zr), Aluminum (Al), Silicon (Si), their oxides or theiralloyed oxides; Hafnium oxides as Hf1-x Ex Oy, where E can be Al, Ca,Ce, Dy, er, Gd, Ge, La, Sc, Si, Sr, Sn, or Y; Al(1-x)Sc(x)N,Ga(1-x)Sc(x)N, Al(1-x)Y(x)N or Al(1-x-y)Mg(x)Nb(y)N, y doped HfO2, wherex includes one of: Al, Ca, Ce, Dy, Er, Gd, Ge, La, Sc, Si, Sr, Sn, or Y,wherein ‘x’ is a fraction; Niobate type compounds LiNbO3, LiTaO3,Lithium iron Tantalum Oxy Fluoride, Barium Strontium Niobate, SodiumBarium Niobate, or Potassium strontium niobate; or an improperferroelectric which includes one of: [PTO/STO]n or [LAO/STO]n, where ‘n’is between 1 to 100.

Example 15: An apparatus comprising: a node; a capacitor comprisingnon-linear polar material, the capacitor having a first terminal coupledto the node and a second terminal coupled to a plate-line, wherein thecapacitor is a planar capacitor; a transistor coupled to the node and abit-line, wherein the transistor is controllable by a word-line, whereinthe plate-line is parallel to the bit-line; a refresh circuitry torefresh charge on the capacitor periodically; and one or morecircuitries to boost the word-line above a voltage supply level during awrite operation and a read operation, wherein the one or morecircuitries is to generate a first pulse on the bit-line after theword-line is boosted and before an end of the boost on the word-lineduring a first write operation, and wherein the one or more circuitriesis to generate a second pulse on the plate-line after the word-line isboosted and before the end of the boost on the word-line during a secondwrite operation different from the first write operation.

Example 16: The apparatus of example 15, wherein the refresh circuitrycomprises logic to improve memory endurance of the capacitor via wearleveling, wherein the wear leveling is applied during read or writeoperations.

Example 17: The apparatus of example 16, wherein the wear levelingincludes a random wear leveling scheme, wherein the refresh circuitry isto apply an outlier compensation scheme before or after the wearleveling.

Example 18: The apparatus of example 15, wherein the planar capacitorcomprises: a first layer coupled to a bottom electrode which is coupledto the node, wherein the first layer comprises a first refractiveinter-metallic material, wherein the first layer extends along anx-plane; a second layer on the first layer, wherein the second layercomprises a first conductive oxide, wherein the second layer extendsalong the x-plane; a third layer comprising the non-linear polarmaterial, wherein the third layer is on the second layer, wherein thethird layer extends along the x-plane; a fourth layer on the thirdlayer, wherein the fourth layer comprises a second conductive oxide,wherein the fourth layer extends along the x-plane; and a fifth layer onthe fourth layer, wherein the fifth layer comprises a second refractiveinter-metallic material, wherein the plate-line is coupled to a portionof the fifth layer.

Example 19: A system comprising: a processor circuitry to execute one ormore instructions; a memory to store the one or more instructions; and acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory includes an apparatus accordingto any one of examples 1 to 14.

Example 20: A system comprising: a processor circuitry to execute one ormore instructions; a memory to store the one or more instructions; and acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory includes an apparatus accordingto any one of examples 15 to 18.

Example 1a: An apparatus comprising: a node; a capacitor comprisingnon-linear polar material, the capacitor having a first terminal coupledto the node and a second terminal coupled to a plate-line, wherein thecapacitor is a pillar capacitor; a transistor coupled to the node and abit-line, wherein the transistor is controllable by a word-line, whereinthe plate-line is parallel to the word-line; and one or more circuitriesto boost the word-line above a voltage supply level during a writeoperation and a read operation, wherein the one or more circuitries isto generate a first pulse on the bit-line after the word-line is boostedand before an end of the boost on the word-line during a first writeoperation, and wherein the one or more circuitries is to generate asecond pulse on the plate-line after the word-line is boosted and beforethe end of the boost on the word-line during a second write operationdifferent from the first write operation.

Example 2a: The apparatus of example 1a, wherein the one or morecircuitries is to generate a third pulse on an unselected bit-line,wherein the third pulse has an amplitude less than a supply level butmore than ground.

Example 3a: The apparatus of example 2a, wherein the third pulse has apulse width which is substantially a pulse width on the word-line.

Example 4a: The apparatus of example 1a, wherein the one or morecircuitries is to force a ground voltage on the bit-line during thesecond write operation.

Example 5a: The apparatus of example 1a, wherein the one or morecircuitries is to initiate a writeback operation after the readoperation.

Example 6a: The apparatus of example 1a, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 7a: The apparatus of example 6a, wherein the one or morecircuitries is to generate a fourth pulse on the plate-line after theword-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the fourth pulse starts when thebit-line is allowed to float.

Example 8a: The apparatus of example 1a, wherein the one or morecircuitries is to boost the word-line by about 0.3V above a voltage onthe bit-line or the plate-line.

Example 9a: The apparatus of example 1a, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the transistor.

Example 10a: The apparatus of example 1a, wherein the transistor is alow leakage transistor.

Example 11a: The apparatus of example 1a comprising a repeater coupledto the plate-line.

Example 12a: The apparatus of example 1a, wherein the transistor is afirst transistor, wherein the apparatus comprises a second transistorhaving a gate terminal coupled to the word-line, wherein the secondterminal of the capacitor is coupled to the plate-line via the secondtransistor, wherein a source terminal of the second transistor iscoupled to the plate-line, wherein a drain terminal of the secondtransistor coupled to the second terminal of the capacitor.

Example 13a: The apparatus of example 1a, wherein when the capacitorcomprises: a first layer comprising a first conducting material, whereinthe first layer is coupled to the first terminal of the capacitor; asecond layer comprising a second conducting material, wherein the secondlayer is around the first layer; a third layer comprising the non-linearpolar material, wherein the third layer is around the second layer; afourth layer comprising a second conducting material, wherein the fourthlayer is around the third layer; and a fifth layer comprising a secondconducting material, wherein the plate-line is partially coupled to thefifth layer.

Example 14a: The apparatus of example 13a, wherein the first layer has afirst circumference, wherein the second layer has a secondcircumference, wherein the third layer has a third circumference,wherein the fourth layer has a fourth circumference, wherein the fifthlayer has a fifth circumference, wherein the fourth circumference islarger than the third circumference, wherein the third circumference islarger than the second circumference, wherein the second circumferenceis larger than the first circumference.

Example 15a: The apparatus of example 1a, wherein the non-linear polarmaterial includes one of ferroelectric material, paraelectric material,or non-linear dielectric.

Example 16a: An apparatus comprising: a node; a capacitor comprisingnon-linear polar material, the capacitor having a first terminal coupledto the node and a second terminal coupled to a plate-line, wherein thecapacitor is a planar capacitor; a transistor coupled to the node and abit-line, wherein the transistor is controllable by a word-line, whereinthe plate-line is parallel to the word-line; and one or more circuitriesto boost the word-line above a voltage supply level during a writeoperation and a read operation, wherein the one or more circuitries isto generate a first pulse on the bit-line after the word-line is boostedand before an end of the boost on the word-line during a first writeoperation, and wherein the one or more circuitries is to generate asecond pulse on the plate-line after the word-line is boosted and beforethe end of the boost on the word-line during a second write operationdifferent from the first write operation.

Example 17a: The apparatus of example 16a, wherein the capacitorcomprises: a first layer coupled to a bottom electrode which is coupledto the node, wherein the first layer comprises a first refractiveinter-metallic material, wherein the first layer extends along anx-plane; a second layer on the first layer, wherein the second layercomprises a first conductive oxide, wherein the second layer extendsalong the x-plane; a third layer comprising the non-linear polarmaterial, wherein the third layer is on the second layer, wherein thethird layer extends along the x-plane; a fourth layer on the thirdlayer, wherein the fourth layer comprises a second conductive oxide,wherein the fourth layer extends along the x-plane; and a fifth layer onthe fourth layer, wherein the fifth layer comprises a second refractiveinter-metallic material, wherein the plate-line is coupled to a portionof the fifth layer.

Example 18a: The apparatus of example 17a, wherein: the first refractiveinter-metallic material and the second refractive inter-metallicmaterial include one or more of Ta, Ti, Al, W, Ni, Ga, Mn, Fe, B, C, Nor Co; and the first conductive oxide and the second conductive oxideinclude one or more of: Ir, In, Fe, Ru, Pd, Os, or Re, wherein theapparatus comprises a sixth layer extending along a y-plane, wherein thesixth layer is adjacent to side walls of the first layer, the secondlayer, the third layer, and the fourth layer, wherein the sixth layerincludes one of: Ti—Al—O, Al2O3, or MgO.

Example 19a: A system comprising: a processor circuitry to execute oneor more instructions; a memory coupled to the processor circuitry,wherein the memory is to store the one or more instructions; and acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory comprises an array of bit-cells,wherein an individual bit-cell includes: a node; a capacitor comprisingnon-linear polar material, the capacitor having a first terminal coupledto the node and a second terminal coupled to a plate-line, wherein thecapacitor is a pillar capacitor; and a transistor coupled to the nodeand a bit-line, wherein the transistor is controllable by a word-line,wherein the plate-line is parallel to the word-line, wherein the memorycomprises: one or more circuitries to boost the word-line above avoltage supply level during a write operation and a read operation,wherein the one or more circuitries is to generate a first pulse on thebit-line after the word-line is boosted and before an end of the booston the word-line, and wherein the one or more circuitries is to generatea second pulse on an unselected bit-line, wherein the second pulse has aduration which is substantially a duration of the first pulse.

Example 20a: The system of example 19a, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the transistor, and wherein an amplitude of the second pulseis between a supply level and ground.

Example 1b: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node and a second terminal coupled to a firstplate-line; a second capacitor comprising non-linear polar material, thesecond capacitor having a first terminal coupled to the node and asecond terminal coupled to a second plate-line; a transistor coupled tothe node and a bit-line, wherein the transistor is controllable by aword-line, wherein the first plate-line and the second plate-line areparallel to the bit-line; and one or more circuitries to boost theword-line above a voltage supply level during a write operation and aread operation, wherein the one or more circuitries is to generate afirst pulse on the bit-line after the word-line is boosted and before anend of the boost on the word-line during a first write operation, andwherein the one or more circuitries is to generate a second pulse on thefirst plate-line after the word-line is boosted and before the end ofthe boost on the word-line during a second write operation differentfrom the first write operation.

Example 2b: The apparatus of example 1b, wherein the one or morecircuitries is to generate a third pulse on the second plate-line,wherein the third pulse has an amplitude less than a supply level butmore than ground.

Example 3b: The apparatus of example 2b, wherein the third pulse has apulse width which is substantially a pulse width on the word-line.

Example 4b: The apparatus of example 1b, wherein the one or morecircuitries is to force a ground voltage on the bit-line during thesecond write operation.

Example 5b: The apparatus of example 1b, wherein the one or morecircuitries is to initiate a writeback operation after the readoperation.

Example 6b: The apparatus of example 1b, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 7b: The apparatus of example 6b, wherein the one or morecircuitries is to generate a fourth pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the fourth pulse starts when thebit-line is allowed to float.

Example 8b: The apparatus of example 7b, wherein the one or morecircuitries is to drive a ground voltage on second plate-line when theone or more circuitries is to generate the fourth pulse on the firstplate-line.

Example 9b: The apparatus of example 1b, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 10b: The apparatus of example 1b, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the transistor.

Example 11b: The apparatus of example 1b comprising a repeater coupledto the word-line.

Example 12b: The apparatus of example 1b, wherein when the firstcapacitor comprises: a first layer comprising a first conductingmaterial, wherein the first layer is coupled to the first terminal ofthe first capacitor; a second layer comprising a second conductingmaterial, wherein the second layer is around the first layer; a thirdlayer comprising the non-linear polar material, wherein the third layeris around the second layer; a fourth layer comprising a secondconducting material, wherein the fourth layer is around the third layer;and a fifth layer comprising a second conducting material, wherein thefirst plate-line is partially coupled to the fifth layer.

Example 13b: The apparatus of example 12b, wherein the first layer has afirst circumference, wherein the second layer has a secondcircumference, wherein the third layer has a third circumference,wherein the fourth layer has a fourth circumference, wherein the fifthlayer has a fifth circumference, wherein the fourth circumference islarger than the third circumference, wherein the third circumference islarger than the second circumference, wherein the second circumferenceis larger than the first circumference.

Example 14b: The apparatus of example 1b, wherein the non-linear polarmaterial includes one of ferroelectric material, paraelectric material,or non-linear dielectric.

Example 15b: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node and a second terminal coupled to a firstplate-line, wherein the first capacitor is a first planar capacitor; asecond capacitor comprising non-linear polar material, the secondcapacitor having a first terminal coupled to the node and a secondterminal coupled to a second plate-line, wherein the second capacitor isa second planar capacitor; a transistor coupled to the node and abit-line, wherein the transistor is controllable by a word-line, whereinthe first plate-line and the second plate-line is parallel to thebit-line; and one or more circuitries to boost the word-line above avoltage supply level during a write operation and a read operation,wherein the one or more circuitries is to generate a first pulse on thebit-line after the word-line is boosted and before an end of the booston the word-line during a first write operation, and wherein the one ormore circuitries is to generate a second pulse on the first plate-lineafter the word-line is boosted and before the end of the boost on theword-line during a second write operation different from the first writeoperation.

Example 16b: The apparatus of example 15b, wherein the first capacitorcomprises: a first layer coupled to a bottom electrode which is coupledto the node, wherein the first layer comprises a first refractiveinter-metallic material, wherein the first layer extends along anx-plane; a second layer on the first layer, wherein the second layercomprises a first conductive oxide, wherein the second layer extendsalong the x-plane; a third layer comprising the non-linear polarmaterial, wherein the third layer is on the second layer, wherein thethird layer extends along the x-plane; a fourth layer on the thirdlayer, wherein the fourth layer comprises a second conductive oxide,wherein the fourth layer extends along the x-plane; and a fifth layer onthe fourth layer, wherein the fifth layer comprises a second refractiveinter-metallic material, wherein the first plate-line is coupled to aportion of the fifth layer.

Example 17b: The apparatus of example 16b, wherein: the first refractiveinter-metallic material and the second refractive inter-metallicmaterial include one or more of Ta, Ti, Al, W, Ni, Ga, Mn, Fe, B, C, Nor Co; and the first conductive oxide and the second conductive oxideinclude one or more of: Ir, In, Fe, Ru, Pd, Os, or Re, wherein theapparatus comprises a sixth layer extending along a y-plane, wherein thesixth layer is adjacent to side walls of the first layer, the secondlayer, the third layer, and the fourth layer, wherein the sixth layerincludes one of: Ti—Al—O, Al2O3, or MgO.

Example 18b: The apparatus of example 15b, wherein the one or morecircuitries is to generate a third pulse on the second plate-line,wherein the third pulse has an amplitude less than a supply level butmore than ground.

Example 19b: A system comprising: a processor circuitry to execute oneor more instructions; a memory coupled to the processor circuitry,wherein the memory is to store the one or more instructions; and acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory comprises an array of bit-cells,wherein an individual bit-cell includes: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node and a second terminal coupled to a firstplate-line; a second capacitor comprising non-linear polar material, thesecond capacitor having a first terminal coupled to the node and asecond terminal coupled to a second plate-line; and a transistor coupledto the node and a bit-line, wherein the transistor is controllable by aword-line, wherein the first plate-line and the second plate-line areparallel to the bit-line, and wherein the memory includes: one or morecircuitries to boost the word-line above a voltage supply level during awrite operation and a read operation, wherein the one or morecircuitries is to generate a first pulse on the bit-line after theword-line is boosted and before an end of the boost on the word-lineduring a first write operation, and wherein the one or more circuitriesis to generate a second pulse on the first plate-line after theword-line is boosted and before the end of the boost on the word-lineduring a second write operation different from the first writeoperation.

Example 20b: The system of example 19b, wherein: the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the transistor; an amplitude of the second pulse is between asupply level and ground; generate a third pulse on the secondplate-line; and the third pulse has an amplitude less than a supplylevel but more than ground.

Example 1c: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node and a second terminal coupled to a firstplate-line; a second capacitor comprising non-linear polar material, thesecond capacitor having a first terminal coupled to the node and asecond terminal coupled to a second plate-line; a transistor coupled tothe node and a bit-line, wherein the transistor is controllable by aword-line, wherein the first plate-line and the second plate-line areparallel to the word-line; and one or more circuitries to boost theword-line above a voltage supply level during a write operation and aread operation, wherein the one or more circuitries is to generate afirst pulse on the bit-line after the word-line is boosted and before anend of the boost on the word-line during a first write operation, andwherein the one or more circuitries is to generate a second pulse on thefirst plate-line within the first pulse.

Example 2c: The apparatus of example 1c, wherein the one or morecircuitries is to force a ground voltage on the bit-line during a secondwrite operation different from the first write operation, wherein theone or more circuitries is to generate the second pulse on the firstplate-line after the word-line is boosted and before an end of the booston the word-line during the second write operation.

Example 3c: The apparatus of example 1c, wherein the one or morecircuitries is to generate a third pulse on the second plate-line,wherein the third pulse has an amplitude less than a supply level butmore than ground.

Example 4c: The apparatus of example 3c, wherein the third pulse has apulse width which is substantially a pulse width on the word-line.

Example 5c: The apparatus of example 1c, wherein the one or morecircuitries is to initiate a writeback operation after the readoperation.

Example 6c: The apparatus of example 1c, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 7c: The apparatus of example 6c, wherein the one or morecircuitries is to generate a fourth pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the fourth pulse starts when thebit-line is allowed to float.

Example 8c: The apparatus of example 7c, wherein the one or morecircuitries is to drive a ground voltage on second plate-line when theone or more circuitries is to generate the fourth pulse on the firstplate-line.

Example 9c: The apparatus of example 1c, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 10c: The apparatus of example 1c, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the transistor.

Example 11c: The apparatus of example 1c comprising a first repeatercoupled to the first plate-line, and a second repeater coupled to thesecond plate-line.

Example 12c: The apparatus of example 1c, wherein when the firstcapacitor comprises: a first layer comprising a first conductingmaterial, wherein the first layer is coupled to the first terminal ofthe first capacitor; a second layer comprising a second conductingmaterial, wherein the second layer is around the first layer; a thirdlayer comprising the non-linear polar material, wherein the third layeris around the second layer; a fourth layer comprising a secondconducting material, wherein the fourth layer is around the third layer;and a fifth layer comprising a second conducting material, wherein thefirst plate-line is partially coupled to the fifth layer.

Example 13c: The apparatus of example 12c, wherein the first layer has afirst circumference, wherein the second layer has a secondcircumference, wherein the third layer has a third circumference,wherein the fourth layer has a fourth circumference, wherein the fifthlayer has a fifth circumference, wherein the fourth circumference islarger than the third circumference, wherein the third circumference islarger than the second circumference, wherein the second circumferenceis larger than the first circumference.

Example 14c: The apparatus of example 1c, wherein the non-linear polarmaterial includes one of a ferroelectric material, paraelectricmaterial, or a non-linear dielectric.

Example 15c: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node and a second terminal coupled to a firstplate-line, wherein the first capacitor is a first planar capacitor; asecond capacitor comprising non-linear polar material, the secondcapacitor having a first terminal coupled to the node and a secondterminal coupled to a second plate-line, wherein the first capacitor isa first planar capacitor; a transistor coupled to the node and abit-line, wherein the transistor is controllable by a word-line, whereinthe first plate-line and the second plate-line are parallel to theword-line; and one or more circuitries to boost the word-line above avoltage supply level during a write operation and a read operation,wherein the one or more circuitries is to generate a first pulse on thebit-line after the word-line is boosted and before an end of the booston the word-line during a first write operation, and wherein the one ormore circuitries is to generate a second pulse on the first plate-linewithin the first pulse.

Example 16c: The apparatus of example 15c, wherein the first capacitorcomprises: a first layer coupled to a bottom electrode which is coupledto the node, wherein the first layer comprises a first refractiveinter-metallic material, wherein the first layer extends along anx-plane; a second layer on the first layer, wherein the second layercomprises a first conductive oxide, wherein the second layer extendsalong the x-plane; a third layer comprising the non-linear polarmaterial, wherein the third layer is on the second layer, wherein thethird layer extends along the x-plane; a fourth layer on the thirdlayer, wherein the fourth layer comprises a second conductive oxide,wherein the fourth layer extends along the x-plane; and a fifth layer onthe fourth layer, wherein the fifth layer comprises a second refractiveinter-metallic material, wherein the first plate-line is coupled to aportion of the fifth layer.

Example 17c: The apparatus of example 16c, wherein: the first refractiveinter-metallic material and the second refractive inter-metallicmaterial include one or more of Ta, Ti, Al, W, Ni, Ga, Mn, Fe, B, C, Nor Co; and the first conductive oxide and the second conductive oxideinclude one or more of: Ir, In, Fe, Ru, Pd, Os, or Re, wherein theapparatus comprises a sixth layer extending along a y-plane, wherein thesixth layer is adjacent to side walls of the first layer, the secondlayer, the third layer, and the fourth layer, wherein the sixth layerincludes one of: Ti—Al—O, Al2O3, or MgO.

Example 18c: The apparatus of example 15c, wherein: the one or morecircuitries is to force a ground voltage on the bit-line during a secondwrite operation different from the first write operation, wherein theone or more circuitries is to generate the second pulse on the firstplate-line after the word-line is boosted and before an end of the booston the word-line during the second write operation; and the one or morecircuitries is to generate a third pulse on the second plate-line,wherein the third pulse has an amplitude less than a supply level butmore than ground.

Example 19c: A system comprising: a processor circuitry to execute oneor more instructions; a memory coupled to the processor circuitry,wherein the memory is to store the one or more instructions; and acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory comprises an array of bit-cells,wherein an individual bit-cell includes: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node and a second terminal coupled to a firstplate-line; a second capacitor comprising non-linear polar material, thesecond capacitor having a first terminal coupled to the node and asecond terminal coupled to a second plate-line; and a transistor coupledto the node and a bit-line, wherein the transistor is controllable by aword-line, wherein the first plate-line and second plate-line areparallel to the word-line, and wherein the memory includes: one or morecircuitries to boost the word-line above a voltage supply level during awrite operation and a read operation, wherein the one or morecircuitries is to generate a first pulse on the bit-line after theword-line is boosted and before an end of the boost on the word-lineduring a first write operation, and wherein the one or more circuitriesis to generate a second pulse on the first plate-line within the firstpulse.

Example 20c: The system of example 19c, wherein: the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the transistor; an amplitude of the second pulse is between asupply level and ground; generate a third pulse on the secondplate-line; and the third pulse has an amplitude less than a supplylevel but more than ground.

Example 1d: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node; a second capacitor comprising thenon-linear polar material, the second capacitor having a first terminalcoupled to the node; a select transistor coupled to the node and abit-line, wherein the select transistor is controllable by a word-line;a first switch coupled to the first capacitor and a first plate-line,the first switch controllable by a first control; a second switchcoupled to the second capacitor and a second plate-line, the secondswitch controllable by a second control; and one or more circuitries toboost the word-line above a voltage supply level during a writeoperation, wherein the one or more circuitries is to control the firstplate-line, the second plate-line, the first control, the secondcontrol, and the bit-line during the write operation.

Example 2d: The apparatus of example 1d, wherein the one or morecircuitries is to generate a first pulse on the bit-line, wherein thefirst pulse has an amplitude lower than the voltage supply level.

Example 3d: The apparatus of example 2d, wherein the one or morecircuitries is to generate a second pulse on the first plate-line,wherein the second pulse starts and ends substantially when the firstpulse starts and ends, wherein the second pulse has an initial amplitudewhich is substantially equal to the amplitude of the first pulse, andwherein the second pulse has an ending amplitude which is substantiallyequal to the amplitude of the first pulse.

Example 4d: The apparatus of example 3d, wherein the one or morecircuitries is to generate a third pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring a first write operation, wherein an amplitude of the third pulseis substantially equal to the voltage supply level.

Example 5d: The apparatus of example 4d, wherein the one or morecircuitries is to generate a fourth pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring a second write operation, wherein an amplitude of the fourthpulse is substantially equal to a ground level, wherein the second writeoperation is differential from the first write operation.

Example 6d: The apparatus of example 3d, wherein the one or morecircuitries is to set a fifth pulse on the second plate-line, whereinthe fifth pulse has an amplitude lower than the voltage supply level,wherein the fifth pulse has a pulse width which is substantially a pulsewidth of the first pulse.

Example 7d: The apparatus of example 1d, wherein the one or morecircuitries is to generate a sixth pulse on the first control, whereinthe sixth pulse has a pulse width which is same as a pulse width on theword-line.

Example 8d: The apparatus of example 7d, wherein the one or morecircuitries is to generate a seventh pulse on the second control,wherein the seventh pulse has a pulse width which is same as the pulsewidth on the word-line.

Example 9d: The apparatus of example 8d, wherein the sixth pulse and theseventh pulse have an amplitude which is substantially equal to theboosted word-line.

Example 10d: The apparatus of example 1d, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 11d: The apparatus of example 1d, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the select transistor.

Example 12d: The apparatus of example 1d, wherein the select transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die.

Example 13d: The apparatus of example 1d, wherein the first capacitorand the second capacitor are planar capacitors or non-planar capacitors.

Example 14d: The apparatus of example 1d, wherein the first capacitorand the second capacitor are vertically stacked.

Example 15d: The apparatus of example 1d comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 16d: The apparatus of example 1d, wherein the bit-line isparallel to the first plate-line and the second plate-line.

Example 17d: The apparatus of example 1d, wherein the non-linear polarmaterial is one of: ferroelectric material, paraelectric material, ornon-linear dielectric.

Example 18d: An apparatus comprising: a node; a plurality of capacitorscoupled to the node, wherein an individual capacitor of the plurality ofcapacitors comprises non-linear polar material; a select transistorcoupled to the node and a bit-line, wherein the select transistor iscontrollable by a word-line; a plurality of switches coupled to theplurality of capacitors, wherein an individual switch is controllable byan individual control; a plurality of plate-lines coupled to theplurality of switches, wherein an individual plate-line is coupled tothe individual switch; and one or more circuitries to boost theword-line above a voltage supply level during a write operation, whereinthe one or more circuitries is to control the individual control, theindividual plate-line, and the bit-line during the write operation.

Example 19d: The apparatus of example 18d, wherein the plurality ofswitches is controlled by a plurality of controls, wherein the pluralityof controls are boosted above the voltage supply level during the writeoperation, wherein the bit-line is parallel to the plurality ofplate-lines.

Example 20d: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 1d to 17d.

Example 21d: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 18d to 19d.

Example 1e: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node; a second capacitor comprising thenon-linear polar material, the second capacitor having a first terminalcoupled to the node; a select transistor coupled to the node and abit-line, wherein the select transistor is controllable by a word-line;a first switch coupled to the first capacitor and a first plate-line,the first switch controllable by a first control; a second switchcoupled to the second capacitor and a second plate-line, the secondswitch controllable by a second control; and one or more circuitries toboost the word-line above a voltage supply level during a readoperation, wherein the one or more circuitries is to control the firstplate-line, the second plate-line, the first control, the secondcontrol, and the bit-line during the read operation.

Example 2e: The apparatus of example 1e, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 3e: The apparatus of example 2e, wherein the one or morecircuitries is to generate a first pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the first pulse starts when thebit-line is allowed to float.

Example 4e: The apparatus of example 3e, wherein the one or morecircuitries is to force a 0V on the second plate-line during the readoperation.

Example 5e: The apparatus of example 3e, wherein the one or morecircuitries is to assert a sense amplifier enable within a pulse widthof the first pulse.

Example 6e: The apparatus of example 1e, wherein the one or morecircuitries is to toggle the word-line from a boosted level to ground,and then back to a boosted level for a writeback operation.

Example 7e: The apparatus of example 1e, wherein: the one or morecircuitries is to generate a third pulse on the first control for aduration of the read operation, wherein the third pulse has an amplitudesubstantially same as an amplitude of the boosted word-line; and the oneor more circuitries is to generate a fourth pulse on the second controlfor a duration of the read operation, wherein the fourth pulse has anamplitude substantially same as an amplitude of the boosted word-line.

Example 8e: The apparatus of example 1e, wherein the one or morecircuitries is to generate a fifth pulse on the bit-line during awriteback operation, wherein the fifth pulse has an amplitude lower thanthe voltage supply level, wherein the writeback operation is part of theread operation.

Example 9e: The apparatus of example 8e, wherein the one or morecircuitries is to generate a sixth pulse on the first plate-line,wherein the sixth pulse starts and ends substantially when the fifthpulse starts and ends, wherein the sixth pulse has an initial amplitudewhich is substantially equal to the amplitude of the fifth pulse, andwherein the sixth pulse has an ending amplitude which is substantiallyequal to the amplitude of the fifth pulse.

Example 10e: The apparatus of example 9e, wherein the one or morecircuitries is to generate a third pulse on the first plate-line afterthe word-line is boosted and before the end of the boost on theword-line during a first writeback operation, wherein an amplitude ofthe third pulse is substantially equal to the voltage supply level.

Example 11e: The apparatus of example 10e, wherein the one or morecircuitries is to generate a seventh pulse on the first plate-line afterthe word-line is boosted and before the end of the boost on theword-line during a second writeback operation, wherein an amplitude ofthe seventh pulse is substantially equal to a ground level, wherein thesecond writeback operation is different from the first writebackoperation.

Example 12e: The apparatus of example 11e, wherein the one or morecircuitries is to set an eighth pulse on the second plate-line duringthe writeback operation, wherein the eighth pulse has an amplitude lowerthan the voltage supply level but above a ground level, wherein theeighth pulse has a pulse width which is substantially a pulse width ofthe fifth pulse.

Example 13e: The apparatus of example 1e, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 14e: The apparatus of example 1e, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the select transistor.

Example 15e: The apparatus of example 1e, wherein the select transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die.

Example 16e: The apparatus of example 1e, wherein: the first capacitorand the second capacitor are planar capacitors or non-planar capacitors;and the first capacitor and the second capacitor are vertically stacked.

Example 17e: The apparatus of example 1e comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 18e: The apparatus of example 1e, wherein the bit-line isparallel to the first plate-line and the second plate-line, and whereinthe non-linear polar material is one of: ferroelectric material,paraelectric material, or non-linear dielectric.

Example 19e: An apparatus comprising: a node; a plurality of capacitorscoupled to the node, wherein an individual capacitor of the plurality ofcapacitors comprises non-linear polar material; a select transistorcoupled to the node and a bit-line, wherein the select transistor iscontrollable by a word-line; a plurality of switches coupled to theplurality of capacitors, wherein an individual switch is controllable byan individual control; a plurality of plate-lines coupled to theplurality of switches, wherein an individual plate-line is coupled tothe individual switch; and one or more circuitries to boost theword-line above a voltage supply level during a read operation, whereinthe one or more circuitries is to control the individual control, theindividual plate-line, and the bit-line during the read operation,wherein the select transistor is on a frontend of a die, and wherein theplurality of switches are on a backend of the die.

Example 20e: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 1e to 18e.

Example 1f: An apparatus comprising: a first node; a second node; afirst capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the first node; a secondcapacitor comprising the non-linear polar material, the second capacitorhaving a first terminal coupled to the first node; a first transistorcoupled to the first node and a bit-line, wherein the first transistoris controllable by a word-line; a first switch coupled to the firstcapacitor and a first plate-line, the first switch controllable by afirst control; a second switch coupled to the second capacitor and asecond plate-line, the second switch controllable by a second control; asecond transistor having a gate terminal coupled to the first node, anda source terminal coupled to a sense-line and a drain terminal coupledto the second node; and one or more circuitries to boost the word-lineabove a voltage supply level during a write operation, wherein the oneor more circuitries is to control the first plate-line, the secondplate-line, the first control, the second control, and the bit-lineduring the write operation.

Example 2f: The apparatus of example 1f, wherein the one or morecircuitries is to generate a first pulse on the bit-line, wherein thefirst pulse has an amplitude lower than the voltage supply level.

Example 3f: The apparatus of example 2f. wherein the one or morecircuitries is to generate a second pulse on the first plate-line,wherein the second pulse starts and ends substantially when the firstpulse starts and ends, wherein the second pulse has an initial amplitudewhich is substantially equal to the amplitude of the first pulse, andwherein the second pulse has an ending amplitude which is substantiallyequal to the amplitude of the first pulse.

Example 4f: The apparatus of example 3f, wherein the one or morecircuitries is to generate a third pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring a first write operation, wherein an amplitude of the third pulseis substantially equal to the voltage supply level.

Example 5f: The apparatus of example 4f, wherein the one or morecircuitries is to generate a fourth pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring a second write operation, wherein an amplitude of the fourthpulse is substantially equal to a ground level, wherein the second writeoperation is differential from the first write operation.

Example 6f: The apparatus of example 3f, wherein the one or morecircuitries is to set a fifth pulse on the second plate-line, whereinthe fifth pulse has an amplitude lower than the voltage supply level,wherein the fifth pulse has a pulse width which is substantially a pulsewidth of the first pulse.

Example 7f: The apparatus of example 1f, wherein the one or morecircuitries is to generate a sixth pulse on the first control, whereinthe sixth pulse has a pulse width which is same as a pulse width on theword-line.

Example 8f: The apparatus of example 7f, wherein the one or morecircuitries is to generate a seventh pulse on the second control,wherein the seventh pulse has a pulse width which is same as the pulsewidth on the word-line.

Example 9f: The apparatus of example 8f, wherein the sixth pulse and theseventh pulse have an amplitude which is substantially equal to theboosted word-line.

Example 10f: The apparatus of example 1f, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 11f: The apparatus of example 1f, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the first transistor.

Example 12f: The apparatus of example 1f, wherein the first transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die.

Example 13f: The apparatus of example 1f, wherein: the first capacitorand the second capacitor are planar capacitors or non-planar capacitors;the first capacitor and the second capacitor are vertically stacked; thesecond node is biased, put on high-impedance state, or set to 0V; andthe sense-line is biased, put on high-impedance state, or set to 0V.

Example 14f: The apparatus of example if comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 15f: The apparatus of example 1f, wherein the bit-line isparallel to the first plate-line and the second plate-line.

Example 16f: The apparatus of example 1f, wherein the non-linear polarmaterial is one of: ferroelectric material, paraelectric material, ornon-linear dielectric.

Example 17f: An apparatus comprising: a first node; a second node; aplurality of capacitors coupled to the first node, wherein an individualcapacitor of the plurality of capacitors comprises non-linear polarmaterial; a first transistor coupled to the first node and a bit-line,wherein the first transistor is controllable by a word-line; a secondtransistor having a gate terminal coupled to the first node, and asource terminal coupled to a sense-line and a drain terminal coupled tothe second node; a plurality of switches coupled to the plurality ofcapacitors, wherein an individual switch is controllable by anindividual control; a plurality of plate-lines coupled to the pluralityof switches, wherein an individual plate-line is coupled to theindividual switch; and one or more circuitries to boost the word-lineabove a voltage supply level during a write operation, wherein the oneor more circuitries is to control the individual control, the individualplate-line, and the bit-line during the write operation.

Example 18f: The apparatus of example 17f, wherein: the plurality ofswitches is controlled by a plurality of controls; the plurality ofcontrols is boosted above the voltage supply level during the writeoperation; the bit-line is parallel to the plurality of plate-lines; thesecond node is biased, put on high-impedance state, or set to 0V; andthe sense-line is biased, put on high-impedance state, or set to 0V.

Example 19f: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 1f to 16f.

Example 19f: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 17f to 18f.

Example 1g: An apparatus comprising: a first node; a second node; afirst capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the first node; a secondcapacitor comprising the non-linear polar material, the second capacitorhaving a first terminal coupled to the first node; a first transistorcoupled to the first node and a bit-line, wherein the first transistoris controllable by a word-line; a first switch coupled to the firstcapacitor and a first plate-line, the first switch controllable by afirst control; a second switch coupled to the second capacitor and asecond plate-line, the second switch controllable by a second control; asecond transistor having a gate terminal coupled to the first node, anda source terminal coupled to a sense-line and a drain terminal coupledto the second node; and one or more circuitries to boost the word-lineabove a voltage supply level during a read operation, wherein the one ormore circuitries is to control the first plate-line, the secondplate-line, the first control, the second control, and the bit-lineduring the read operation.

Example 2g: The apparatus of example 1g, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 3g: The apparatus of example 2g, wherein the one or morecircuitries is to generate a first pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the first pulse starts when thebit-line is allowed to float.

Example 4g: The apparatus of example 3g, wherein the one or morecircuitries is to force a 0V on the second plate-line during the readoperation.

Example 5g: The apparatus of example 3g, wherein the one or morecircuitries is to assert a sense amplifier enable within a pulse widthof the first pulse.

Example 6g: The apparatus of example 1g, wherein the one or morecircuitries is to toggle the word-line from a boosted level to ground,and then back to a boosted level for a writeback operation.

Example 7g: The apparatus of example 1g, wherein: the one or morecircuitries is to generate a third pulse on the first control for aduration of the read operation, wherein the third pulse has an amplitudesubstantially same as an amplitude of the boosted word-line; and the oneor more circuitries is to generate a fourth pulse on the second controlfor a duration of the read operation, wherein the fourth pulse has anamplitude substantially same as an amplitude of the boosted word-line.

Example 8g: The apparatus of example 1g, wherein the one or morecircuitries is to generate a fifth pulse on the bit-line during awriteback operation, wherein the fifth pulse has an amplitude lower thanthe voltage supply level, wherein the writeback operation is part of theread operation.

Example 9g: The apparatus of example 8g, wherein the one or morecircuitries is to generate a sixth pulse on the first plate-line,wherein the sixth pulse has an initial amplitude which is substantiallyequal to the amplitude of the fifth pulse, and wherein the sixth pulsehas an ending amplitude which is substantially equal to the amplitude ofthe fifth pulse.

Example 10g: The apparatus of example 9g, wherein the one or morecircuitries is to generate a third pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring a first writeback operation, wherein an amplitude of the thirdpulse is substantially equal to the voltage supply level.

Example 11g: The apparatus of example 10g, wherein the one or morecircuitries is to generate a seventh pulse on the first plate-line afterthe word-line is boosted and before the end of the boost on theword-line during a second writeback operation, wherein an amplitude ofthe seventh pulse is substantially equal to a ground level, wherein thesecond writeback operation is different from the first writebackoperation.

Example 12g: The apparatus of example 11g, wherein the one or morecircuitries is to set an eighth pulse on the second plate-line duringthe writeback operation, wherein the eighth pulse has an amplitude lowerthan the voltage supply level but above a ground level, wherein theeighth pulse has a pulse width which is substantially a pulse width ofthe fifth pulse.

Example 13g: The apparatus of example 1g, wherein: the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the first transistor; and the first transistor is on afrontend of a die, and wherein the first switch and the second switchare on a backend of the die.

Example 14g: The apparatus of example 1g, wherein: the first capacitorand the second capacitor are planar capacitors or non-planar capacitors;and the first capacitor and the second capacitor are vertically stacked.

Example 15g: The apparatus of example 1g comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 16g: The apparatus of example 1g, wherein the bit-line isparallel to the first plate-line and the second plate-line, and whereinthe non-linear polar material is one of: ferroelectric material,paraelectric material, or non-linear dielectric.

Example 17g: An apparatus comprising: a first node; a second node; aplurality of capacitors coupled to the first node, wherein an individualcapacitor of the plurality of capacitors comprises non-linear polarmaterial; a first transistor coupled to the first node and a bit-line,wherein the first transistor is controllable by a word-line; a secondtransistor having a gate terminal coupled to the first node, and asource terminal coupled to a sense-line and a drain terminal coupled tothe second node; a plurality of switches coupled to the plurality ofcapacitors, wherein an individual switch is controllable by anindividual control; a plurality of plate-lines coupled to the pluralityof switches, wherein an individual plate-line is coupled to theindividual switch; and one or more circuitries to boost the word-lineabove a voltage supply level during a read operation, wherein the one ormore circuitries is to control the individual control, the individualplate-line, and the bit-line during the read operation.

Example 18g: The apparatus of example 17g, wherein: the plurality ofswitches is controlled by a plurality of controls; the plurality ofcontrols is boosted above the voltage supply level during the readoperation; the bit-line is parallel to the plurality of plate-lines; thesecond node is biased, put on high-impedance state, or set to 0V; andthe sense-line is biased, put on high-impedance state, or set to 0V.

Example 19g: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 1g to 16g.

Example 19g: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 17g to 18g.

Example 1h: An apparatus comprising: a first node; a second node; afirst capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the first node and a secondterminal coupled to a first plate-line; a second capacitor comprisingthe non-linear polar material, the second capacitor having a firstterminal coupled to the first node and a second terminal coupled to asecond plate-line; a first transistor coupled to the first node and abit-line, wherein the first transistor is controllable by a word-line,wherein the first plate-line and the second plate-line are parallel tothe word-line; a second transistor having a gate terminal coupled to thefirst node, and a source terminal coupled to a sense-line and a drainterminal coupled to the second node; and one or more circuitries toboost the word-line during a write operation.

Example 2h: The apparatus of example 1h, wherein the one or morecircuitries is to boost the word-line above a voltage supply level,wherein the one or more circuitries is to generate a first pulse on thebit-line after the word-line is boosted and before an end of the booston the word-line during a first write operation.

Example 3h: The apparatus of example 2h, wherein the one or morecircuitries is to generate a second pulse on the first plate-line afterthe word-line is boosted and before the end of the boost on theword-line during a second write operation different from the first writeoperation.

Example 4h: The apparatus of example 2h, wherein the one or morecircuitries is to generate a third pulse on the second plate-line,wherein an amplitude of the third pulse is lower than an amplitude onthe word-line.

Example 5h: The apparatus of example 4h, wherein the amplitude of thethird pulse is half of a supply voltage level.

Example 6h: The apparatus of example 1h, wherein unselected plate-linesand word-lines are set to ground voltage during the write operation.

Example 7h: The apparatus of example 1h, wherein the one or morecircuitries include a repeater for the first plate-line and the secondplate-line.

Example 8h: The apparatus of example 1h, wherein the first capacitor andthe second capacitor are planar capacitors that are vertically stacked.

Example 9h: The apparatus of example 1h, wherein the first capacitorcomprises: a first layer coupled to the first terminal of the firstcapacitor, wherein the first layer in on a first metal layer whichextends out to couple to a first via; a second layer around the firstlayer; a third layer comprising the non-linear polar material, whereinthe third layer is around the second layer; a fourth layer around thethird layer; and a fifth layer, wherein the first plate-line ispartially coupled to the fifth layer.

Example 10h: The apparatus of example 9h, wherein the second capacitorcomprises: a first layer coupled to the first terminal of the secondcapacitor, wherein the first layer of the second capacitor in on asecond metal layer which extends out to couple to a second via, whereinthe second via is on the first via; a second layer around the firstlayer of the second capacitor; a third layer comprising the non-linearpolar material, wherein the third layer of the second capacitor isaround the second layer of the second capacitor; a fourth layer aroundthe third layer of the second capacitor; and a fifth layer, wherein thesecond plate-line is partially coupled to the fifth layer of the secondcapacitor.

Example 11h: The apparatus of example 1h, wherein the first transistorand the second transistor are of a same conductivity type.

Example 12h: The apparatus of example 1h, wherein the first transistorand the second transistor are one of planar transistors or non-planartransistors.

Example 13h: The apparatus of example 1h, wherein the sense-line is setto one of: 0V, a high-impedance state, or a bias voltage, and whereinthe second node is set to one of: 0V, a high-impedance state, or a biasvoltage.

Example 14h: The apparatus of example 1h, wherein the non-linear polarmaterial includes one of: ferroelectric material, paraelectric material,or non-linear dielectric.

Example 15h: An apparatus comprising: a multi-element gain bit-cellcomprising: a first capacitor having non-linear polar material, thefirst capacitor having a first terminal coupled to a node and a secondterminal coupled to a first plate-line; a second capacitor comprisingthe non-linear polar material, the second capacitor having a firstterminal coupled to the node and a second terminal coupled to a secondplate-line; and two transistors connected to the node, wherein a firsttransistor of the two transistors is controlled by a voltage on thenode, while a second transistor of the two transistors is controlled bya word-line, wherein the second transistor is coupled to a bit-line; andone or more circuitries to control the bit-line, word-line, the firstplate-line, and the second plate-line to perform a write operation onthe multi-element gain bit-cell.

Example 16h: The apparatus of example 15h, wherein the one or morecircuitries to boost the word-line during a write operation.

Example 17h: The apparatus of example 15h, wherein unselectedplate-lines and word-lines are set to ground voltage during the writeoperation.

Example 18h: A system comprising: a processor circuitry to execute oneor more instructions; a memory coupled to the processor circuitry,wherein the memory is to store the one or more instructions; acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory includes an apparatus accordingto any one of examples 1h to 14h.

Example 18h: A system comprising: a processor circuitry to execute oneor more instructions; a memory coupled to the processor circuitry,wherein the memory is to store the one or more instructions; acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory includes an apparatus accordingto any one of examples 15h to 17h.

Example 1i: An apparatus comprising: a first node; a second node; afirst capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the first node and a secondterminal coupled to a first plate-line; a second capacitor comprisingthe non-linear polar material, the second capacitor having a firstterminal coupled to the first node and a second terminal coupled to asecond plate-line; a first transistor coupled to the first node and abit-line, wherein the first transistor is controllable by a word-line,wherein the first plate-line and the second plate-line are parallel tothe word-line; a second transistor having a gate terminal coupled to thefirst node, and a source terminal coupled to a sense-line and a drainterminal coupled to the second node; and one or more circuitries toboost the word-line during a read operation.

Example 2i: The apparatus of example 1i, wherein the one or morecircuitries is to boost the word-line above a voltage supply level for afirst time period and then discharged to ground, wherein the one or morecircuitries is to boost the word-line above the voltage supply levelduring a writeback operation, wherein the writeback operation is part ofthe read operation.

Example 3i: The apparatus of example 1i, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 4i: The apparatus of example 3i, wherein the one or morecircuitries is to allow the bit-line to float when the boosted word-lineis discharged to ground.

Example 5i: The apparatus of example 1i, wherein the one or morecircuitries is to pre-charge the sense-line, thereafter the one or morecircuitries is to put the sense-line in a high-impedance state.

Example 6i: The apparatus of example 2i, wherein the one or morecircuitries is to generate a first pulse on the first plate-line afterthe word-line is boosted and discharged during the read operation,wherein the first pulse starts when the bit-line is allowed to float.

Example 7i: The apparatus of example 7i, wherein the one or morecircuitries is to force a 0V on the second plate-line during the readoperation.

Example 8i: The apparatus of example 7i, wherein the one or morecircuitries is to assert a sense amplifier enable within a pulse widthof the first pulse.

Example 9i: The apparatus of example 2i, wherein the one or morecircuitries is to generate a second pulse on the bit-line after theword-line is boosted and before an end of the boost on the word-lineduring the writeback operation for a first write operation.

Example 10i: The apparatus of example 9i, wherein the one or morecircuitries is to generate a third pulse on the first plate-line afterthe word-line is boosted and before the end of the boost on theword-line during the writeback operation for a second write operationdifferent from the first write operation.

Example 11i: The apparatus of example 9i, wherein the one or morecircuitries is to generate a fourth pulse on the second plate-line,wherein an amplitude of the third pulse is lower than an amplitude onthe word-line.

Example 12i: The apparatus of example 11i, wherein the amplitude of thefourth pulse is half of a supply voltage level.

Example 13i: The apparatus of example 1i, wherein unselected plate-linesand word-lines are set to ground voltage during the read operation.

Example 14i: The apparatus of example 1i, wherein the one or morecircuitries include a repeater for the first plate-line and the secondplate-line.

Example 15i: The apparatus of example 1i, wherein the first capacitorand the second capacitor are planar capacitors that are verticallystacked.

Example 16i: The apparatus of example 1i, wherein: the first transistorand the second transistor are of a same conductivity type; and the firsttransistor and the second transistor are one of planar transistors ornon-planar transistors.

Example 17i: The apparatus of example 2i, wherein during the writebackoperation, the one or more circuitries is to set the sense-line to oneof: 0V, a high-impedance state, or a bias voltage, wherein during thewriteback operation, the one or more circuitries is to set the secondnode to one of: 0V, a high-impedance state, or a bias voltage.

Example 18i: The apparatus of example 1i, wherein the non-linear polarmaterial includes one of: ferroelectric material, paraelectric material,or non-linear dielectric.

Example 19i: An apparatus comprising: a multi-element gain bit-cellcomprising: a first capacitor having non-linear polar material, thefirst capacitor having a first terminal coupled to a node and a secondterminal coupled to a first plate-line; a second capacitor comprisingthe non-linear polar material, the second capacitor having a firstterminal coupled to the node and a second terminal coupled to a secondplate-line; and two transistors connected to the node, wherein a firsttransistor of the two transistors is controlled by a voltage on thenode, while a second transistor of the two transistors is controlled bya word-line, wherein the second transistor is coupled to a bit-line; andone or more circuitries to control the bit-line, word-line, the firstplate-line, and the second plate-line to perform a read operation on themulti-element gain bit-cell.

Example 20i: A system comprising: a processor circuitry to execute oneor more instructions; a memory coupled to the processor circuitry,wherein the memory is to store the one or more instructions; acommunication interface to allow the processor circuitry to communicatewith another device, wherein the memory includes an apparatus accordingto any one of examples 1i to 18i.

Example 1j: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node; a second capacitor comprising thenon-linear polar material, the second capacitor having a first terminalcoupled to the node; a select transistor coupled to the node and abit-line, wherein the select transistor is controllable by a word-line;a first switch coupled to the first capacitor and a first plate-line,the first switch controllable by a first control; a second switchcoupled to the second capacitor and a second plate-line, the secondswitch controllable by a second control; and one or more circuitries toboost the word-line above a voltage supply level during a writeoperation, wherein the one or more circuitries is to cause a voltagedrop across one of the first capacitor or the second capacitor, betweentwo different write operations, to be the voltage supply level.

Example 2j: The apparatus of example 1j, wherein the write operationincludes a first write operation and a second write operation, whereinthe one or more circuitries is to generate a first pulse on the bit-linefor a first write operation, wherein the first pulse has an amplitude ofthe voltage supply level.

Example 3j: The apparatus of example 2j, wherein the one or morecircuitries is to apply a 0V on the bit-line for a second writeoperation different from the first write operation.

Example 4j: The apparatus of example 3j, wherein the one or morecircuitries is to apply a second pulse on the first plate-line for thesecond write operation, wherein the second pulse has an amplitude of thevoltage supply level.

Example 5j: The apparatus of example 3j, wherein the one or morecircuitries is to apply a 0V on the first plate-line for the first writeoperation.

Example 6j: The apparatus of example 4j, wherein the second pulse startsand ends substantially when the first pulse starts and ends.

Example 7j: The apparatus of example 1j, wherein the one or morecircuitries is to generate a third pulse on the first control, whereinthe third pulse has a pulse width which is same as a pulse width on theword-line.

Example 8j: The apparatus of example 7j, wherein the one or morecircuitries is to apply a 0V on the second control.

Example 9j: The apparatus of example 7j, wherein the third pulse has anamplitude which is substantially equal to the boosted word-line.

Example 10j: The apparatus of example 1j, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 11j: The apparatus of example 1j, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the select transistor.

Example 12j: The apparatus of example 1j, wherein the select transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die.

Example 13j: The apparatus of example 1j, wherein the first capacitorand the second capacitor are planar capacitors or non-planar capacitors.

Example 14j: The apparatus of example 1j, wherein the first capacitorand the second capacitor are vertically stacked.

Example 15j: The apparatus of example 1j comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 16j: The apparatus of example 1j, wherein the bit-line isparallel to the first plate-line and the second plate-line.

Example 17j: The apparatus of example 1j, wherein the non-linear polarmaterial is one of: ferroelectric material, paraelectric material, ornon-linear dielectric.

Example 18j: An apparatus comprising: a node; a plurality of capacitorscoupled to the node, wherein an individual capacitor of the plurality ofcapacitors comprises non-linear polar material; a select transistorcoupled to the node and a bit-line, wherein the select transistor iscontrollable by a word-line; a plurality of switches coupled to theplurality of capacitors, wherein an individual switch is controllable byan individual control; a plurality of plate-lines coupled to theplurality of switches, wherein an individual plate-line is coupled tothe individual switch; and one or more circuitries to boost theword-line above a voltage supply level during a write operation, whereinthe one or more circuitries is to cause a voltage drop across one of theindividual capacitor of the plurality of capacitors, between twodifferent write operations, to be the voltage supply level or negativevoltage supply level, and wherein the one or more circuitries is tocontrol the individual control, the individual plate-line, and thebit-line during the write operation.

Example 19j: The apparatus of example 18j, wherein the plurality ofswitches is controlled by a plurality of controls, wherein theindividual control is boosted above the voltage supply level during thewrite operation, wherein the bit-line is parallel to the plurality ofplate-lines.

Example 20j: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 1j to 17j.

Example 1k: An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node; a second capacitor comprising thenon-linear polar material, the second capacitor having a first terminalcoupled to the node; a select transistor coupled to the node and abit-line, wherein the select transistor is controllable by a word-line;a first switch coupled to the first capacitor and a first plate-line,the first switch controllable by a first control; a second switchcoupled to the second capacitor and a second plate-line, the secondswitch controllable by a second control; and one or more circuitries toboost the word-line above a voltage supply level during a readoperation, wherein the one or more circuitries is to cause a voltagedrop across one of the first capacitor or the second capacitor, betweentwo different write operations, to be the voltage supply level or anegative of the voltage supply level, and wherein the two differentwrite operations are part of a writeback operation which is part of theread operation.

Example 2k: The apparatus of example 1k, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 3k: The apparatus of example 2k, wherein the one or morecircuitries is to generate a first pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the first pulse starts when thebit-line is allowed to float.

Example 4k: The apparatus of example 3k, wherein the one or morecircuitries is to force a 0V on the second plate-line during the readoperation.

Example 5k: The apparatus of example 3k, wherein the one or morecircuitries is to assert a sense amplifier enable within a pulse widthof the first pulse.

Example 6k: The apparatus of example 1k, wherein the one or morecircuitries is to toggle the word-line from a boosted level to groundafter the writeback operation completes.

Example 7k: The apparatus of example 1k, wherein: the one or morecircuitries is to generate a third pulse on the first control for aduration of the read operation, wherein the third pulse has an amplitudesubstantially same as an amplitude of the boosted word-line; and the oneor more circuitries is to set a ground voltage on the second control fora duration of the read operation.

Example 8k: The apparatus of example 1k, wherein the one or morecircuitries is to generate a fifth pulse on the bit-line during awriteback operation for a first write operation, wherein the fifth pulsehas an amplitude of the voltage supply level.

Example 9k: The apparatus of example 8k, wherein the one or morecircuitries is to generate a sixth pulse on the first plate-line for asecond write operation different from the first write operation.

Example 10k: The apparatus of example 1k, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 11k: The apparatus of example 1k, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the select transistor.

Example 12k: The apparatus of example 1k, wherein the select transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die.

Example 13k: The apparatus of example 1k, wherein: the first capacitorand the second capacitor are planar capacitors or non-planar capacitors;and the first capacitor and the second capacitor are vertically stacked.

Example 14k: The apparatus of example 1k comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 15k: The apparatus of example 1k, wherein the bit-line isparallel to the first plate-line and the second plate-line, and whereinthe non-linear polar material is one of: ferroelectric material,paraelectric material, or non-linear dielectric.

Example 16k: An apparatus comprising: a node; a plurality of capacitorscoupled to the node, wherein an individual capacitor of the plurality ofcapacitors comprises non-linear polar material; a select transistorcoupled to the node and a bit-line, wherein the select transistor iscontrollable by a word-line; a plurality of switches coupled to theplurality of capacitors, wherein an individual switch is controllable byan individual control; a plurality of plate-lines coupled to theplurality of switches, wherein an individual plate-line is coupled tothe individual switch; and one or more circuitries to boost theword-line above a voltage supply level during a read operation, whereinthe one or more circuitries is to cause a voltage drop across theindividual capacitor, between two different write operations, to be thevoltage supply level or a negative voltage supply level, and wherein thetwo different write operations are part of a writeback operation whichis part of the read operation, and wherein the one or more circuitriesis to control the individual control, the individual plate-line, and thebit-line during the read operation.

Example 17k: The apparatus of example 16k, wherein the bit-line isparallel to the individual plate-line and the individual plate-line, andwherein the non-linear polar material is one of: ferroelectric material,paraelectric material, or non-linear dielectric.

Example 18k: The apparatus of example 16k, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 19k: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises an apparatusaccording to any one of examples 1k to 15k, wherein the one or morecircuitries is to ensure maximum electrical field across the individualcapacitor, between two different write operations.

Example 1l: An apparatus comprising: a first node; a second node; afirst capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the first node; a secondcapacitor comprising the non-linear polar material, the second capacitorhaving a first terminal coupled to the first node; a first transistorcoupled to the first node and a bit-line, wherein the first transistoris controllable by a word-line; a second transistor having a gateterminal coupled to the first node, and a source terminal coupled to asense-line and a drain terminal coupled to the second node; a firstswitch coupled to the first capacitor and a first plate-line, the firstswitch controllable by a first control; a second switch coupled to thesecond capacitor and a second plate-line, the second switch controllableby a second control; and one or more circuitries to boost the word-lineabove a voltage supply level during a write operation, wherein the oneor more circuitries is to cause a voltage drop across one of the firstcapacitor or the second capacitor, between two different writeoperations, to be the voltage supply level or a negative voltage supplylevel.

Example 2l: The apparatus of example 1j, wherein the write operationincludes a first write operation and a second write operation, whereinthe one or more circuitries is to generate a first pulse on the bit-linefor a first write operation, wherein the first pulse has an amplitude ofthe voltage supply level.

Example 3l: The apparatus of example 2l, wherein the one or morecircuitries is to apply a 0V on the bit-line for the second writeoperation different from the first write operation.

Example 4l: The apparatus of example 3l, wherein the one or morecircuitries is to apply a second pulse on the first plate-line for thesecond write operation, wherein the second pulse has an amplitude of thevoltage supply level.

Example 5l: The apparatus of example 3l, wherein the one or morecircuitries is to apply a 0V on the first plate-line for the first writeoperation.

Example 6l: The apparatus of example 4l, wherein the second pulse startsand ends substantially when the first pulse starts and ends.

Example 7l: The apparatus of example 1l, wherein the one or morecircuitries is to generate a third pulse on the first control, whereinthe third pulse has a pulse width which is same as a pulse width on theword-line.

Example 8l: The apparatus of example 7l, wherein the one or morecircuitries is to apply a 0V on the second control.

Example 9l: The apparatus of example 7l, wherein the third pulse has anamplitude which is substantially equal to the boosted word-line.

Example 10l: The apparatus of example 1l, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 11l: The apparatus of example 1l, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the first transistor.

Example 12l: The apparatus of example 1l, wherein: the first transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die; the first capacitor and the secondcapacitor are planar capacitors or non-planar capacitors; the secondnode is biased, put on high-impedance state, or set to 0V; and thesense-line is biased, put on high-impedance state, or set to 0V.

Example 13l: The apparatus of example 1l, wherein the first capacitorand the second capacitor are vertically stacked.

Example 14l: The apparatus of example 1l comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 15l: The apparatus of example 1l, wherein the bit-line isparallel to the first plate-line and the second plate-line.

Example 16l: The apparatus of example 1l, wherein the non-linear polarmaterial is one of: ferroelectric material, paraelectric material, ornon-linear dielectric.

Example 17l: An apparatus comprising: a first node; a second node; aplurality of capacitors coupled to the first node, wherein an individualcapacitor of the plurality of capacitors comprises non-linear polarmaterial; a first transistor coupled to the first node and a bit-line,wherein the first transistor is controllable by a word-line; a secondtransistor having a gate terminal coupled to the first node, and asource terminal coupled to a sense-line and a drain terminal coupled tothe second node; a plurality of switches coupled to the plurality ofcapacitors, wherein an individual switch is controllable by anindividual control; a plurality of plate-lines coupled to the pluralityof switches, wherein an individual plate-line is coupled to theindividual switch; and one or more circuitries to boost the word-lineabove a voltage supply level during a write operation, wherein the oneor more circuitries is to cause a voltage drop across the individualcapacitor of a plurality of capacitors, between two different writeoperations, to be the voltage supply level or a negative voltage supplylevel, and wherein the one or more circuitries is to control theindividual control, the individual plate-line, and the bit-line duringthe write operation.

Example 18l: The apparatus of example 17l, wherein the plurality ofswitches is controlled by a plurality of controls, wherein theindividual control is boosted above the voltage supply level during thewrite operation, wherein the bit-line is parallel to the plurality ofplate-lines.

Example 19l: The apparatus of example 17l, wherein: the second node isbiased, put on high-impedance state, or set to 0V; and the sense-line isbiased, put on high-impedance state, or set to 0V.

Example 20l: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises: a first node; asecond node; a first capacitor comprising non-linear polar material, thefirst capacitor having a first terminal coupled to the first node; asecond capacitor comprising the non-linear polar material, the secondcapacitor having a first terminal coupled to the first node; a firsttransistor coupled to the first node and a bit-line, wherein the firsttransistor is controllable by a word-line; a second transistor having agate terminal coupled to the first node, and a source terminal coupledto a sense-line and a drain terminal coupled to the second node; a firstswitch coupled to the first capacitor and a first plate-line, the firstswitch controllable by a first control; a second switch coupled to thesecond capacitor and a second plate-line, the second switch controllableby a second control; and one or more circuitries to boost the word-lineabove a voltage supply level during a write operation, wherein the oneor more circuitries is to ensure a maximum electrical field across thefirst capacitor or the second capacitor, between two different writeoperations.

Example 1m: An apparatus comprising: a first node; a second node; afirst capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the first node; a secondcapacitor comprising the non-linear polar material, the second capacitorhaving a first terminal coupled to the first node; a first transistorcoupled to the first node and a bit-line, wherein the first transistoris controllable by a word-line; a first switch coupled to the firstcapacitor and a first plate-line, the first switch controllable by afirst control; a second switch coupled to the second capacitor and asecond plate-line, the second switch controllable by a second control; asecond transistor having a gate terminal coupled to the first node, anda source terminal coupled to a sense-line and a drain terminal coupledto the second node; and one or more circuitries to boost the word-lineabove a voltage supply level during a read operation, wherein the one ormore circuitries is to cause a voltage drop across one of the firstcapacitor or the second capacitor, between two different writeoperations, to be the voltage supply level, and wherein the twodifferent write operations are part of a writeback operation which ispart of the read operation.

Example 2m: The apparatus of example 1m, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 3m: The apparatus of example 2m, wherein the one or morecircuitries is to generate a first pulse on the first plate-line afterthe word-line is boosted and before an end of the boost on the word-lineduring the read operation, wherein the first pulse starts when thebit-line is allowed to float.

Example 5m: The apparatus of example 3m, wherein the one or morecircuitries is to force a 0V on the second plate-line during the readoperation.

Example 6m: The apparatus of example 3m, wherein the one or morecircuitries is to assert a sense amplifier enable within a pulse widthof the first pulse.

Example 6m: The apparatus of example 1m, wherein the one or morecircuitries is to toggle the word-line from a boosted level to groundafter the writeback operation completes.

Example 7m: The apparatus of example 1, wherein: the one or morecircuitries is to generate a third pulse on the first control for aduration of the read operation, wherein the third pulse has an amplitudesubstantially same as an amplitude of the boosted word-line; and the oneor more circuitries is to set a ground voltage on the second control fora duration of the read operation.

Example 8m: The apparatus of example 1m, wherein the one or morecircuitries is to generate a fifth pulse on the bit-line during awriteback operation for a first write operation, wherein the fifth pulsehas an amplitude of the voltage supply level.

Example 9m: The apparatus of example 8m, wherein the one or morecircuitries is to generate a sixth pulse on the first plate-line for asecond write operation different from the first write operation.

Example 10m: The apparatus of example 1m, wherein the one or morecircuitries is to boost the word-line by about 0.3V above the voltagesupply level.

Example 11m: The apparatus of example 1m, wherein the one or morecircuitries is to boost the word-line by about 1.5× of a thresholdvoltage of the first transistor.

Example 12m: The apparatus of example 1m, wherein the first transistoris on a frontend of a die, and wherein the first switch and the secondswitch are on a backend of the die.

Example 13m: The apparatus of example 1m, wherein: the first capacitorand the second capacitor are planar capacitors or non-planar capacitors;the first capacitor and the second capacitor are vertically stacked; thesecond node is biased, put on high-impedance state, or set to 0V; andthe sense-line is biased, put on high-impedance state, or set to 0V.

Example 14m: The apparatus of example 1m comprising a refresh circuitryto refresh charges on the first capacitor and the second capacitor.

Example 15m: The apparatus of example 1m, wherein the bit-line isparallel to the first plate-line and the second plate-line, and whereinthe non-linear polar material is one of: ferroelectric material,paraelectric material, or non-linear dielectric.

Example 16m: An apparatus comprising: a first node; a second node; aplurality of capacitors coupled to the first node, wherein an individualcapacitor of the plurality of capacitors comprises non-linear polarmaterial; a first transistor coupled to the first node and a bit-line,wherein the first transistor is controllable by a word-line; a secondtransistor having a gate terminal coupled to the first node, and asource terminal coupled to a sense-line and a drain terminal coupled tothe second node; a plurality of switches coupled to the plurality ofcapacitors, wherein an individual switch is controllable by anindividual control; a plurality of plate-lines coupled to the pluralityof switches, wherein an individual plate-line is coupled to theindividual switch; and one or more circuitries to boost the word-lineabove a voltage supply level during a read operation, wherein the one ormore circuitries is to cause a voltage drop across the individualcapacitor, between two different write operations, to be the voltagesupply level, and wherein the two different write operations are part ofa writeback operation which is part of the read operation.

Example 17m: The apparatus of example 16m, wherein the bit-line isparallel to the individual plate-line and the individual plate-line, andwherein the non-linear polar material is one of: ferroelectric material,paraelectric material, or non-linear dielectric.

Example 18m: The apparatus of example 16m, wherein the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation.

Example 19m: A system comprising: a processor circuitry to execute oneor more instructions; a communication interface to allow the processorcircuitry to communicate with another device; and a memory coupled tothe processor circuitry, wherein the memory comprises: a first node; asecond node; a first capacitor comprising non-linear polar material, thefirst capacitor having a first terminal coupled to the first node; asecond capacitor comprising the non-linear polar material, the secondcapacitor having a first terminal coupled to the first node; a firsttransistor coupled to the first node and a bit-line, wherein the firsttransistor is controllable by a word-line; a first switch coupled to thefirst capacitor and a first plate-line, the first switch controllable bya first control; a second switch coupled to the second capacitor and asecond plate-line, the second switch controllable by a second control; asecond transistor having a gate terminal coupled to the first node, anda source terminal coupled to a sense-line and a drain terminal coupledto the second node; and one or more circuitries to boost the word-lineabove a voltage supply level during a read operation, wherein the one ormore circuitries is to cause a voltage drop across one of the firstcapacitor or the second capacitor, between two different writeoperations, to be the voltage supply level, and wherein the twodifferent write operations are part of a writeback operation which ispart of the read operation.

Example 20m: The system of example 19m, wherein: the one or morecircuitries is to initially force a voltage on the bit-line andsubsequently allow the bit-line to float during the read operation; theone or more circuitries is to generate a first pulse on the firstplate-line after the word-line is boosted and before an end of the booston the word-line during the read operation; the first pulse starts whenthe bit-line is allowed to float; the second node is biased, put on ahigh-impedance state, or set to 0V; the sense-line is biased, put on ahigh-impedance state, or set to 0V; and the bit-line is parallel to thefirst plate-line and the second plate-line.

An abstract is provided that will allow the reader to ascertain thenature and gist of the technical disclosure. The abstract is submittedwith the understanding that it will not be used to limit the scope ormeaning of the claims. The following claims are hereby incorporated intothe detailed description, with each claim standing on its own as aseparate embodiment.

We claim:
 1. An apparatus comprising: a node; a first capacitorcomprising non-linear polar material, the first capacitor having a firstterminal coupled to the node; a second capacitor comprising thenon-linear polar material, the second capacitor having a first terminalcoupled to the node; a select transistor coupled to the node and abit-line, wherein the select transistor is controllable by a word-line;a first switch coupled to the first capacitor and a first plate-line,the first switch controllable by a first control; a second switchcoupled to the second capacitor and a second plate-line, the secondswitch controllable by a second control; and one or more circuitries toboost a voltage on the word-line above a voltage supply level during awrite operation, wherein the one or more circuitries is to cause avoltage drop across one of the first capacitor or the second capacitor,between two different write operations, to be the voltage supply levelor a negative voltage supply level.
 2. The apparatus of claim 1, whereinthe write operation includes a first write operation and a second writeoperation, wherein the one or more circuitries is to generate a firstpulse on the bit-line for the first write operation, and wherein thefirst pulse has a first amplitude which is an amplitude of the voltagesupply level.
 3. The apparatus of claim 2, wherein the one or morecircuitries is to apply a 0V on the bit-line for the second writeoperation different from the first write operation.
 4. The apparatus ofclaim 3, wherein the one or more circuitries is to apply a second pulseon the first plate-line for the second write operation, and wherein thesecond pulse has a second amplitude which is the amplitude of thevoltage supply level.
 5. The apparatus of claim 3, wherein the one ormore circuitries is to apply a 0V on the first plate-line for the firstwrite operation.
 6. The apparatus of claim 4, wherein the second pulsestarts and ends substantially when the first pulse starts and ends. 7.The apparatus of claim 1, wherein the one or more circuitries is togenerate a third pulse on the first control, and wherein the third pulsehas a pulse width which is same as a pulse width on the word-line. 8.The apparatus of claim 7, wherein the one or more circuitries is toapply a 0V on the second control.
 9. The apparatus of claim 7, whereinthe third pulse has an amplitude which is substantially equal to theboosted voltage of the word-line.
 10. The apparatus of claim 1, whereinthe one or more circuitries is to boost voltage of the word-line byabout 0.3V above the voltage supply level.
 11. The apparatus of claim 1,wherein the one or more circuitries is to boost voltage of the word-lineby about 1.5× of a threshold voltage of the select transistor.
 12. Theapparatus of claim 1, wherein the select transistor is on a frontend ofa die, and wherein the first switch and the second switch are on abackend of the die.
 13. The apparatus of claim 1, wherein the firstcapacitor and the second capacitor are planar capacitors or non-planarcapacitors.
 14. The apparatus of claim 1, wherein the first capacitorand the second capacitor are vertically stacked.
 15. The apparatus ofclaim 1 comprising a refresh circuitry to refresh charges on the firstcapacitor and the second capacitor.
 16. The apparatus of claim 1,wherein the bit-line is parallel to the first plate-line and the secondplate-line.
 17. The apparatus of claim 1, wherein the non-linear polarmaterial is one of: ferroelectric material, paraelectric material, ornon-linear dielectric.
 18. An apparatus comprising: a node; a pluralityof capacitors coupled to the node, wherein an individual capacitor ofthe plurality of capacitors comprises non-linear polar material; aselect transistor coupled to the node and a bit-line, wherein the selecttransistor is controllable by a word-line; a plurality of switchescoupled to the plurality of capacitors, wherein an individual switch iscontrollable by an individual control; a plurality of plate-linescoupled to the plurality of switches, wherein an individual plate-lineis coupled to the individual switch; and one or more circuitries toboost a voltage on the word-line above a voltage supply level during awrite operation, wherein the one or more circuitries is to cause avoltage drop across one of the individual capacitor of the plurality ofcapacitors, between two different write operations, to be the voltagesupply level or a negative voltage supply level, and wherein the one ormore circuitries is to control the individual control, the individualplate-line, and the bit-line during the write operation.
 19. Theapparatus of claim 18, wherein the plurality of switches is controlledby a plurality of controls, and wherein a voltage of the individualcontrol is boosted above the voltage supply level during the writeoperation, wherein the bit-line is parallel to the plurality ofplate-lines.
 20. A system comprising: a processor circuitry to executeone or more instructions; a communication interface to allow theprocessor circuitry to communicate with another device; and a memorycoupled to the processor circuitry, wherein the memory comprises: anode; a first capacitor comprising non-linear polar material, the firstcapacitor having a first terminal coupled to the node; a secondcapacitor comprising the non-linear polar material, the second capacitorhaving a first terminal coupled to the node; a select transistor coupledto the node and a bit-line, wherein the select transistor iscontrollable by a word-line; a first switch coupled to the firstcapacitor and a first plate-line, the first switch controllable by afirst control; a second switch coupled to the second capacitor and asecond plate-line, the second switch controllable by a second control;and one or more circuitries to boost a voltage of the word-line above avoltage supply level during a write operation, wherein the one or morecircuitries is to ensure a maximum electrical field across the firstcapacitor or the second capacitor, between two different writeoperations.